Methods for treating cancer using cytokine-expressing polynucleotides

ABSTRACT

The present invention provides a pharmaceutical composition, comprising a non-infectious, non-integrating polynucleotide construct comprising a polynucleotide encoding an interferon ω and one or more cationic compounds. The present invention also provides methods of treating cancer in a mammal, comprising administering into a muscle of the mammal a non-infectious, non-integrating DNA polynucleotide construct comprising a polynucleotide encoding a cytokine. In addition, the present invention also relates to the methodology for selective transfection of malignant cells with polynucleotides expressing therapeutic or prophylactic molecules in intra-cavity tumor bearing mammals. More specifically, the present invention provides a methodology for the suppression of an intra-cavity dissemination of malignant cells, such as intraperitoneal dissemination. Furthermore, the invention relates to compositions and methods to deliver polynucleotides encoding polypeptides to vertebrate cells in vivo, where the composition comprises an aqueous solution of sodium phosphate.

This application claims the benefit of the filing date of the followingprovisional applications: 60/067,087 filed Nov. 20, 1997; 60/079,914,filed Mar. 30, 1998; and 60/100,820, filed Sep. 15, 1998, all of whichare incorporated herein by reference. This application is acontinuation-in-part of U.S. patent application Ser. No. 09/196,313,filed Nov. 20, 1998, now abandoned which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to treatment of cancer in mammals.Generally, the present invention provides methods of treating cancer ina mammal by administering a polynucleotide construct comprising apolynucleotide encoding a cytokine. In addition, the present inventionrelates to the methodology for selective transfection of malignant cellswith polynucleotides expressing therapeutic or prophylactic molecules inintra-cavity tumor bearing mammals. More specifically, the presentinvention provides a methodology for the suppression of an intra-cavitydissemination of malignant cells, such as intraperitoneal dissemination.

The present invention further relates generally to compositions andmethods useful for in vivo polynucleotide-based polypeptide deliveryinto cells of vertebrates. More particularly, the present inventionprovides the use of sodium phosphate solutions in compositions andmethods useful for direct polynucleotide-based polypeptide delivery intothe cells of vertebrates.

2. Related Art

Cytokines have been demonstrated both in pre-clinical animal models aswell as in humans to have potent anti-tumor effects. In particular IFN'shave been tried for the treatment of a number of human concerns.

The interferons (IFNs) are a family of cytokines with potent anti-viral,antiproliferative, and immunomodulatory activities and play importantroles in the body's defensive response to viruses, bacteria, and tumors(Baron, S. et al., JAMA 266:1375 (1991)). On the basis of antigenicity,biochemical properties, and producer cell, the interferon's have beendivided into two classes, type I interferon and type II interferon.IFNα, IFNβ, IFNω, and IFNτ are type I interferons, and bind to the sameα/β receptor. IFNγ is a type II interferon, and binds to the γ receptor(Pestka, S., Ann. Rev. Biochem. 56:727 (1987)). IFNα and IFNβ arenaturally expressed in many cells upon viral infection. IFNγ is producedby activated T lymphocytes and natural killer (NK) cells. IFNτ isbelieved to possess hormone activity, and plays an important role inpregnancy in cattle, sheep, and related ruminants (Imakawa, K. et al.,Nature 330:377 (1987); Stewart, H. J. et al., J. Endocrinology 115:R13(1987)). Due to the pleiotropic activities of IFNs, these cytokines havebeen studied for their therapeutic efficacy in a number of diseases,particularly cancers and viral infectious diseases.

IFNω was discovered independently by three different groups in 1985(Capon, D. J., et al., Molec. Cell. Biol. 5: 768-779 (1985), Feinstein,S. et al., Molec. Cell. Biol 5:510 (1985); and Hauptmann and Swetly,Nucl. Acids Res. 13: 4739-4749 (1985)). Unlike IFNα, for which at least14 different functional nonallelic genes have been identified in man,IFNω is encoded by a single functional gene. IFNω genes are believed tobe present in most mammals, but have not been found in dogs, rats ormice. The mature IFNω polypeptide is 172 amino acids and shares 60%sequence homology with the human IFNα's. Due to the sequence similaritywith IFNα, IFNω was originally considered to be a member or a subfamilyof IFNα, and was originally termed IFNα-_(II). IFNω is a significantcomponent (≈10%) of human leukocyte-derived interferon, the naturalmixture of interferon produced after viral infection (Adolf, G. et al.,Virology 175:410 (1990)). IFNω has been demonstrated to bind to the sameα/β receptor as IFNα (Flores, I. et al., J. Biol. Chem. 266: 19875-19877(1991)), and to share similar biological activities with IFNα, includinganti-proliferative activity against tumor cells in vitro (Kubes, M. etal., J. Interferon Research 14:57 (1994) and immunomodulatory activity(Nieroda et al., Molec. Cell. Differentiation 4: 335-351 (1996)).

Recombinant IFNα polypeptide has been approved for use in humans forhairy cell leukemia, AIDS-related Kaposi's sarcoma, malignant melanoma,chronic hepatitis B and C, chronic myleogenous leukemia, and condylomataacuminata (Baron, S. et al., JAMA266:1375 (1991)). However, for each ofthese indications, IFNα polypeptide must be administered repeatedly,often on a daily basis, for extended periods of time to maintaineffective serum levels due to the short half-life (hours) of thepolypeptide in the serum (Friedman, Interferons: A Primer, AcademicPress, New York, pp. 104-107 (1981); Galvani and Cawley, CytokineTherapy, Cambridge University Press, Cambridge, pp. 114-115 (1992)).Thus, in spite of producing clinical benefit for many diseaseconditions, the use of IFNα polypeptide is associated with acute andchronic side effects in most patients (Jones, Cancer 57: 1709-1715(1986); and Quesda et al., Blood 68: 493-497 (1986)). The severity ofthe adverse reaction correlates with peak serum interferon levels.

Viral or plasmid vectors containing IFNα genes have been used in ex vivotherapy to treat mouse tumors. For example, tumor cells were transfectedin vitro with viral or plasmid vectors containing an IFNα gene, and thetransfected tumor cells were injected into mice (Belldegrun, A., et al.,J. Natl. Cancer Inst. 85: 207-216 (1993); Ferrantini, M. et al., CancerResearch 53: 1107-1112 (1993); Ferrantini, M. et al., J. Immunology 153:4604-4615 (1994); Kaido, T. et al., Int. J. Cancer 60: 221-229 (1995);Ogura, H. et al., Cancer Research 50: 5102-5106 (1990); Santodonato, L.,et al., Human Gene Therapy 7:1-10 (1996); Santodonato, L., et al., GeneTherapy 4:1246-1255 (1997)). In another ex vivo study, cervicalcarcinoma and leukemia cells were transfected with a viral vectorcontaining the interferon-consensus gene, and the transfected cells wereinjected into mice (Zhang, J.-F. et al., Cancer Gene Therapy 3: 31-38(1996)). In all of these ex vivo studies, varying levels of anti-tumorefficacy, such as tumor regression and/or prolonged survival, have beenobserved.

Viral or plasmid vectors containing interferon genes have also been usedin in vivo therapy for tumor-bearing mice. For example, a viral vectorcontaining the interferon-consensus gene was injected into mice bearingtransplanted MDA-MB-435 breast cancer, hamster melanoma, or K562leukemia, and tumor regression was reported (Zhang, J.-F. et al., Proc.Natl. Acad. Sci. USA 93: 4513-4518 (1996)). In a similar study, aplasmid vector containing human IFNβ gene complexed with cationic lipidwas injected intracranially into mice bearing a human glioma, and tumorregression was reported (Yagi, K. et al., Biochemistry and MolecularBiology International 32: 167-171 (1994)). In a murine model of renalcell carcinoma the direct intratumoral injection of an IL-2 plasmidDNA:lipid complex has been shown to result in complete tumor regressionand a significant induction of a tumor specific CTL response increase insurvival (Saffran et al., Cancer Gene Therapy 5: 321-330 (1998)).

Plasmid vectors containing cytokine genes have also been reported toresult in systemic levels of the encoded cytokine and in some cases,biological effects characteristic of each cytokine in mice. For example,the intramuscular injection of plasmid DNA encoding either TGFβ, IL-2,IL-4, IL-5, or IFNα resulted in physiologically significant amounts inthe systemic circulation of the corresponding cytokine polypeptide (Raz,E. et al., Proc. Natl. Acad. Sci. USA 90: 4523-4527 (1993); Raz, E. etal., Lupus 4: 266-292 (1995); Tokui, M. et al., Biochem. Biophys. Res.Comm. 233: 527-531 (1997); Lawson, C. et al., J. Interferon CytokineRes. 17: 255-261 (1997); Yeow, W.-S. et al., J. Immunol. 160: 2932-2939(1998)).

U.S. Pat. No. 5,676,954 reports on the injection of genetic material,complexed with cationic liposomes carriers, into mice. U.S. Pat. Nos.4,897,355; 4,946,787; 5,049,386; 5,459,127; 5,589,466; 5,693,622;5.580,859; 5,703,055; and International Patent Application No.PCT/US94/06069 (publication no. WO 94/29469) provide cationic lipids foruse in transfecting DNA into cells and mammals. U.S. Pat. Nos.5,589,466, 5.693,622, 5,580,859, 5,703,055, and international patentapplication no. PCT/US94/06069 (publication no. WO 04/9469) providemethods for delivering DNA-cationic lipid complexes to mammals.

Even though some viral vectors used in ex vivo and in vivo cancertherapy in murine models showed anti-tumor efficacy, the use of viralvectors to deliver interferon-expressing genes in vivo could induceanti-viral immune responses or result in viral integration into hostchromosomes, causing disruption of essential host genes or activation ofoncogenes (Ross et al. Human Gene Therapy 7: 1781-1790 (1996)).

For treatment of multiple metastatic carcinomas of a body cavity aretreated using laparoscopy (Childers et al, Gynecol. Oncol. 59: 25-33.(1995)), catheterization (Naumann et al, Gynecol. Oncol. 50: 291-3,(1993)) or other access devices (Almadrones et al, Semin. Oncol. Nurs.11: 194-202, (1995)). Treatment is usually by surgical removal ofprimary and large metastatic tumors and postoperative chemotherapy(Kigwawa et al, Am. J. Clin. Oncol. 17: 230-3, (1994); Markman et al, J.Clin. Oncol. 10: 1485-91. (1992)) or radiotherapy (Fjeld et al, Acta.Obstet. Gynecol. Scand. Suppl. 155: 105-11. (1992)). Tumor recurrence ismonitored by magnetic resonance imaging (Forstner et al, Radiology 196:715-20, (1995)), ascites cytology (Clement, Am. J. Clin. Pathol. 103:673-6, (1995); Forstner et al, Radiology 196: 715-20, 1995) and bloodanalyses (Forstner et al, Radiology 196: 715-20. (1995)). Manyintraperitoneal (i.p.) cancers, such as ovarian cancer, eventuallymetastasize via the lymphatic system to the lungs or other vital organs,and the prognosis for the patient is very poor (Kataoka et al, NipponSanka Fujinka Gakkai Zasshi 46: 337-44, 1994; Hamilton, Curr. Probl.Cancer 16: 1-57. (1992)).

Human ovarian cancer is often diagnosed at an advanced stage when theeffectiveness of surgery and chemotherapy are limited. The lack ofeffective treatment options for late-stage patients warrants thedevelopment of new treatment modalities for this disease. There havebeen several attempts to develop an effective immunotherapy for thetreatment of ovarian cancer.

The early work in this area involved mouse studies in whichbacteria-derived immunostimulants, such as Bacillus Calmette-Guerin(BCG) and Corynebacterium parvum, were injected i.p. as non-specificactivators of the immune system. (Knapp and Berkowitz, Am. J. Obstet.Gynecol., 128: 782-786, (1977); Bast et al., J. Immunol., 123:1945-1951, (1979); Vanhaelen, et al., Cancer Research, 41: 980-983,(1981); and Berek, et al., Cancer Research, 44, 1871-1875, (1984)).These studies generally resulted in a non-specific immune response thatoften did not prevent the growth of later tumors. In addition, if thebacterial antigens were injected more than 24 hours after tumor cellinoculation, there was minimal antitumor response, suggesting thattreatment of late-stage ovarian cancer patients with this type oftherapy would not be effective.

More recent studies in both mice and humans have involved the i.p. orintravenous (i.v.) administration of cytokine proteins as more specificactivators of the immune response (Adachi, et al, Cancer Immunol.Immunother. 37: 1-6, (1993); Lissoni, et al, Tumori. 78: 118-20,(1992)). Treating murine ovarian tumors with a combination ofrecombinant IL-2 and GM-CSF proteins had some beneficial effect ininhibiting ascites production; however, IL-2 was only effective if itwas combined with GM-CSF (Kikuchi, et al., Cancer Immunol. Immunother.,43: 257-261, (1996)). Similarly, a combination of IL-2 andlymphokine-activated killer (LAK) cells was able to reduce i.p. sarcomasin mice, while IL-2 protein alone was not as effective (Ottow, et al.,Cellular Immunology, 104: 366-376, (1987)). Human clinical trialsevaluating IL-2 protein therapy of ovarian cancer patients indicatedsome antitumor effects (Chapman et al., Investigational New Drugs,6:179-188. (1988); West et al. N. Engl. J. Med. 316:898-905, 1987; Lotzeet al., Arch. Surg. 121:1373-1379, 1986; Benedetti Panici et al., CancerTreatment Review, 16A:123-127, 1989; Beller et al., Gynecol. Oncol.,34:407-412, 1989; Urba et al., J. Natl. Cancer Inst., 81:602-611, 1989;Stewart et al., Cancer Res., 50:6302-6310, 1990; Steis et al., J. Clin.Oncol., 8:1618-1629, 1990; Lissoni et al., Tumori, 78:118-120, 1992;Sparano et al., J. of Immunotherapy, 16:216-223, 1994; Freedman et al.,J. of Immunotherapy, 16:198-210, 1994; Edwards et al., J. Clin. Oncol.,15:3399-3407, 1997).

Recent studies in mice have involved the injection of DNA constructsencoding “suicide” genes followed by treatment with prodrugs. Thisapproach has successfully caused regression of some small tumors but hasbeen less successful on larger tumor masses. (Szala, et al. Gene Therapy3: 1025-1031, 1996; Sugaya, et al. Hum Gene Ther 7: 223-230 (1996)). Inanother study, liposome-mediated E1A gene therapy for mice bearingovarian cancers that overexpress HER-2/neu resulted in reduced mortalityamong these tumor bearing mice. (Yu, et al. Oncogene, 11: 1383-1388(1995)). Similarly, the successful treatment of murine ovarian carcinoma(MOT) has been demonstrated using cisplatin-induced gene transfer of DNAconstructs encoding IFNγ via i.p. injection. (Son, Cancer Gene Therapy4: 391-396 (1997)). However, this study demonstrated that tumors werepoorly responsive to either the IFNγ gene or cisplatin alone, suggestingthat the effectiveness of the cisplatin-based gene therapy protocol wasmainly due to enhanced sensitization of cisplatin-exposed tumor cells totransfection by the IFNγ gene. (Son, Cancer Gene Therapy 4: 391-396,1997).

Clearly, there is a need for superior therapeutic compositions andmethods for treating mammalian cancer. Further, there is a need for anin vivo delivery system for IFNω. The present invention provides asimple and safe yet effective compositions and methods for treatment ofmammalian cancer.

The present invention also solves the problems inherent in priorattempts to treat body cavity malignancies. The inventors show hereinthat the malignant cell dissemination into body cavities, such as intothe peritoneal cavity during late stage ovarian cancer, can besuppressed simply by administering as few as two to six doses of apolynucleotide formulation directly into the body cavity. This treatmentresults in selective transfection of malignant cells, and subsequentlong-term local production of an effective amount of therapeuticmolecules.

The in vivo delivery of a polynucleotide (e.g., plasmid DNA) intovertebrate tissues has been shown to result in the cellular uptake andexpression of the polynucleotide into a desired polypeptide (Wolff, J.A. et al., Science 247:1465-1468 (1990); Wheeler, C. J. et al., Proc.Natl. Acad. Sci. USA 93:11454-11459 (1996)). Potential human therapeuticuses of such polynucleotide-based polypeptide delivery include immuneresponse induction and modulation, therapeutic polypeptide delivery, andamelioration of genetic defects. For example, a polynucleotide mayencode an antigen that induces an immune response against an infectiouspathogen or against tumor cells (Restifo, N. P. et al., Folia Biol.40:74-88 (1994); Ulmer, J. B. et al., Ann. NY Acad. Sci. 772:117-125(1995); Horton, H. M. et al., Proc. Natl. Acad. Sci. USA 96:1553-1558(1999); Yagi, K. et al., Hum. Gene Ther. 10: 1975-1982 (1999)). Thepolynucleotide may encode an immunomodulatory polypeptide, e.g., acytokine, that diminishes an immune response against self antigens ormodifies the immune response to foreign antigens, allergens, ortransplanted tissues (Qin, L. et al., Ann. Surg. 220:508-518 (1994);Dalesandro, J. et al., J. Thorac. Cardiovasc. Surg. 111: 416-421 (1996);Moffatt, M. and Cookson, W., Nat. Med. 2:515-516 (1996); Ragno, S. etal., Arth. and Rheum. 40:277-283 (1997); Dow, S. W. et al., Hum. GeneTher. 10:1905-1914 (1999); Piccirillo, C. A. et al., J. Immunol.161:3950-3956 (1998); Piccirillo, C. A. and Prud'homme, G. J., Hum. GeneTher. 10: 915-1922 (1999)). For therapeutic polypeptide delivery, thepolynucleotide may encode, for example, an angiogenic protein, hormone,growth factor, or enzyme (Levy, M. Y. et al., Gene Ther. 3:201-211(1996); Tripathy, S. K. et al., Proc. Natl. Acad. Sci. USA93:10876-10880 (1996); Tsurumi, Y. et al., Circulation 94:3281-3290(1996); Novo, F. J. et al., Gene Ther. 4:488-492 (1997); Baumgartner, I.et al., Circulation 97:1114-1123 (1998); Mir, L. M. et al., Proc. Natl.Acad. Sci. USA 96:4262-4267 (1999)). For amelioration of geneticdefects, the polynucleotide may encode normal copies of defectiveproteins such as dystrophin or cystic fibrosis transmembrane conductanceregulator (Danko, I. et al., Hum. Mol. Genet. 2:2055-2061 (1993); Cheng,S. H. and Scheule, R. K., Adv. Drug Deliv. Rev. 30:173-184 (1998)).

However, the efficiency of a polynucleotide uptake and expression,especially when the polynucleotide is not associated with infectiousagents, is relatively low. For example, Doh, S. G. et al., Gene Ther.4:648-663 (1997) reports that the administration of plasmid DNA intomouse muscle results in the detectable transduction of an average ofonly 6%, e.g., about 234 out of approximately 4000, of the myofibers inthe injected muscle. Wheeler, C. G. et al., ibid., showed thatadministration of plasmid DNA complexed with cationic lipid into a mouselung results in the transduction of less than 1% of the lung cells.

Attempts have been made to increase the efficiency of in vivopolynucleotide administration into vertebrates using chemical agents orphysical manipulations. Such chemical agents include cellular toxinssuch as bupivacaine or barium chloride (Wells, D. J., FEBS Letters332:179-182 (1993); Vitadello, M. et al., Hum. Gene. Ther. 5:11-18(1994); Danko, I. et al., Hum. Mol. Genet. 2:2055-2061 (1993)) which actto cause muscle damage followed by muscle regeneration by cell divisionwhich makes the cells more receptive to DNA entry (Thomason, D. B. andBooth, F. W., Am. J. Physiol. 258:C578-81 (1990)); polymers such aspolyvinyl pyrollidine that coat the DNA and protect it from DNases(Mumper, R. J., et al., Pharm. Res. 13:701-709 (1996); Mumper R. J. etal., J. Cont. Rel. 52:191-203 (1998); Anwer, K. et al., Pharm. Res.16:889-95 (1999)); bulking agents such as sucrose that are injectedbefore DNA injection to help expand the spaces between muscle cells andtherefore allow better distribution of the subsequently injected DNA(Davis, H. L. et al., Hum. Gene Ther. 4:151-159 (1993)); DNA bindingagents such as histones or intercalaters that protect the DNA fromDNases (Manthorpe, M. et al., Hum. Gene Ther. 4:419-431 (1993); Wolff.J. A., Neuromuscul. Disord. 7:314-318 (1997); WO 99/31262). Physicalmanipulations include removal of nerves that control muscle contraction(Wolff, J. A. et al., BioTechniques 11:575-485 (1991)); electroporationthat electrically opens muscle cell pores allowing more DNA entry(Aihara, H. and Miyazaki, J., Nature Biotechnol. 16:867-870 (1998); Mir,L. M. et al. CR Acad. Sci. III 321:893-899 (1998), Mir, L. M. et al.,Proc. Natl. Acad. Sci. USA 96:4262-4267 (1999); Mathiesen, I., GeneTher. 6:508-514 (1999); Rizzuto, G. et al., Proc. Natl. Acad. Sci. USA96:6417-6422 (1999)); use of intravascular pressure (Budker, V. et al.,Gene Ther. 5:272-276 (1998)); use of sutures coated with plasmid DNA(Labhasetwar, V. et al., J. Pharm. Sci. 87:1347-1350 (1998); Qin, Y. etal., Life Sci. 65:2193-2203 (1999)); use of sponges soaked with DNA asintramuscular depots to prolong DNA delivery (Wolff, J. A. et al.(1991), ibid.); use of special needle-based injection methods (Levy, M.Y. et al., Gene Ther. 3:201-211 (1996); Doh, S. G. et al. (1997),ibid.); and of needleless-injectors that propel the DNA into cells(Gramzinski, R. A. et al., Molec. Med. 4:109-118 (1998); Smith, B. F. etal., Gene Ther. 5:865-868 (1998); Anwer, K. et al. (1999) ibid.). Inaddition, Wolff, J. A. et al. (1991) ibid. and Manthorpe, M. et al.(1993) ibid. refers to conditions affecting direct gene transfer intorodent muscle in vivo.

WO99/64615 identifies the use of products and methods useful fordelivering formulated nucleic acid molecules using electrical pulsevoltage delivery. Examples include the formulation of plasmid DNA in asaline solution containing agents that promote better delivery of theplasmid DNA into cells in vivo when the formulation is delivered with anelectrical pulse. Electrical pulse delivery often compriseselectroporation where an electrical pulse is delivered to a tissue thatis previously injected with a drug. Electroporation of a tissue causestransient interruption of cell membranes allowing more drug to enter thecell through the interruptions or “pores”. The agents in the saline DNAsolution that promote delivery of the DNA into electroporated tissuesinclude propylene glycols, polyethylene glycols, poloxamers (blockcopolymers of propylene oxide and ethylene oxide), or cationic lipids.They claim that the way that these agents enhance deliver % of the DNAinto cells is by either protecting the DNA from degradation by DNases orby condensing the DNA into a smaller form, or both.

Many of these attempts to enhance tissue transduction have used agentsthat destroy muscle (bupivacaine, barium chloride) and actually lowerexpression (Norman, J. et al., Methods in Molec. Med. 29:185-196(1999)); have to be pre-injected before the DNA (sucrose); are expensiveorganic polymers (polyvinyl pyrollidine), mutagens (intercalaters),antigenic proteins (histones) or devices that destroy muscle tissue(needless or needle-free injectors); or need to be inserted surgically(sutures, sponges, intravascular pressure). Furthermore, most of thesemethods may be expensive and not suitable or practical for human use.

On the other hand, little attention has been given to the use ofalternative salt solutions and/or auxiliary agents in the pharmaceuticalformulation as a way of enhancing the efficiency of apolynucleotide-based polypeptide delivery. Investigators in this fieldroutinely use normal saline or phosphate buffered saline (PBS 0.9%(i.e., about 154 mM) NaCl and 10 mM Na-phosphate) solutions forpolynucleotide delivery, e.g., by intramuscular injection, because theyare physiologically isotonic, isoosmotic, stable, non-toxic, and alsobecause they have been traditionally used for human intramuscularinjections of other drugs. However, sodium phosphate, in the absence ofsaline, has been used in humans for delivery of non-polynucleotide-baseddrugs (e.g., small molecules) administered via the intramuscular orintravenous routes (See generally, Physician's Desk Reference. MedicalEconomics Co, Monyvale, N.J. (1998)).

Sodium or potassium phosphate have been reported to enhanceLipofectin™-mediated transfection of human osteosarcoma cells in vitro(Kariko, K., et al., Biochim Biophys Acta 1369:320-334 (1998)), and theuse of RPMI cell culture medium buffered with NaHCO₃/Na₂HPO₄ werereported to be the best medium for forming DNA/cationic lipid complexesin vitro. (Kichler, A., et al., Gene Ther. 5:855-860 (1998)).

There remains a need in the art for a convenient and safe way ofimproving the effectiveness of in vivo polypeptide delivery via directadministration of a polynucleotide. Aqueous solutions of certain saltsincluding sodium phosphate have been used in humans (i.e., intramuscularinjection of various small molecule drugs), and detergents orsurfactants as auxiliary agents are common additives in drugsadministered into human tissues. However, the use of certain salts orauxiliary agents, or a combination thereof to improve the transduction,i.e., the entry into cells, and/or expression-enhancing efficiency ofpolynucleotides delivered in vivo is new.

SUMMARY OF THE INVENTION

The present invention is broadly directed to treatment of cancer byadministering in vivo, into a tissue of a mammal suffering from cancer,a polynucleotide construct comprising a polynucleotide encoding acytokine. The polynucleotide construct is incorporated into the cells ofthe mammal in vivo, and a therapeutically effective amount of a cytokineis produced in vivo, and delivered to tumor cells. Combinations ofcytokine-encoding polynucleotides can be administered.

The present invention provides a pharmaceutical composition comprisingabout 1 ng to 20 mg of a non-infectious, non-integrating polynucleotideconstruct comprising a polynucleotide selected from the group consistingof (a) a polynucleotide that hybridizes under stringent conditions tothe nucleotide sequence of SEQ ID No. 7 or the complement thereof,wherein the polynucleotide sequence encodes a polypeptide that hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; (b)a polynucleotide that encodes a polypeptide comprising an amino acidsequence which, except for at least one but not more than 20 amino acidsubstitutions, deletions, or insertions, is identical to amino acids −23to 172 or 1 to 172 in SEQ ID No. 8, wherein the polypeptide hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; and(c) a polynucleotide that encodes a polypeptide comprising amino acids86-172 in SEQ ID No. 8, wherein the polypeptide has antiproliferativeactivity when added to NIH-OVCAR3 cells in vitro; and any of the abovegroup complexed with one or more cationic compounds selected from thegroup consisting of cationic lipids, cationic peptides, cationicproteins, cationic polymers, and mixtures thereof.

The present invention also provides a pharmaceutical compositionobtained by complexing a polynucleotide selected from the groupconsisting of (a) a polynucleotide that hybridizes under stringentconditions to the nucleotide sequence of SEQ ID No. 7 or the complementthereof, wherein the polynucleotide sequence encodes a polypeptide thathas antiproliferative activity when added to NIH-OVCAR3 cells in vitro;(b) a polynucleotide that encodes a polypeptide comprising an amino acidsequence which, except for at least one but not more than 20 amino acidsubstitutions, deletions, or insertions, is identical to amino acids −23to 172 or 1 to 172 in SEQ ID No. 8, wherein the polypeptide hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; (c)a polynucleotide that encodes a polypeptide comprising amino acids86-172 in SEQ ID No. 8, wherein the polypeptide has antiproliferativeactivity when added to NIH-OVCAR3 cells in vitro, with one or morecationic compounds selected from the group consisting of cationiclipids, cationic peptides, cationic proteins, cationic polymers, andmixtures thereof.

The present invention also provides a method of treating cancer in amammal, comprising administering into a tissue of the mammal anon-infectious, non-integrating polynucleotide construct comprising apolynucleotide encoding a cytokine, or an active fragment thereof, suchthat the polynucleotide is expressed in vivo, and such that thecytokine, or active fragment thereof, is delivered systemically to atumor tissue in an amount effective to treat the cancer.

The present invention also provides a method of treating cancer in amammal, comprising administering into a tissue of the mammal anon-infectious, non-integrating polynucleotide construct comprising apolynucleotide encoding a cytokine selected from the group consisting ofinterferon-ω, interferon-α, and a combination thereof, such that thepolynucleotide or an active fragment thereof is expressed, and such thatthe cytokine is delivered locally to a tumor tissue in an amounteffective to treat the cancer. Preferably, the polynucleotide constructis complexed with a cationic vehicle, more preferably, the cationicvehicle may be a cationic lipid, and most preferably, the cationic lipidmay be mixed with a neutral lipid.

Another object of the invention is to provide a method of selectivelytransfecting malignant cells in a body cavity of a tumor-bearing mammal,comprising administering into the body cavity at least onenon-infectious, non-integrating polynucleotide complexed with a cationicvehicle, such that the polynucleotide is expressed substantially in themalignant cells of the body cavity. Preferably, the cationic vehiclecomprises one or more cationic lipids, and more preferably, the cationicvehicle comprises a cationic and neutral lipid mixture. In a preferredembodiment, the present invention is used to suppress peritonealdissemination of malignant cells in a tumor-bearing mammal. Inparticular, the mammal may have ovarian cancer, or metastasis of ovariancancer. Preferred polynucleotides may encode cytokines, or activefragments thereof. Most preferably, the polynucleotide may encode IL-2,or an active fragment thereof.

Compared to injection of recombinant cytokine polypeptides, the methodsdescribed herein have several important advantages. The presentinvention shows that in vivo transfection of cells with encodingpolynucleotide, such as an IL-2 or IFNω, results in serum levels of thecorresponding cytokine that have therapeutic effects, and yet are lowerthan the maximal serum levels typically required when cytokinepolypeptides are injected. Further, injecting frequent high doses ofcytokine polypeptides can produce debilitating side effects. The methodsof the present invention provide cytokine therapy requiring lessfrequent injections of cytokine-encoding nucleic acids. The injection ofpolynucleotide constructs encoding cytokines produces sustained, lowlevels of biologically active cytokines that have beneficial effects,while minimizing adverse side effects.

Compared to the delivery of cytokine genes via a viral gene deliveryvectors, the present method also has important advantages. Injection ofnon-viral vectors of the present method does not induce significanttoxicity or pathological immune responses, as described, for example, inmice, pigs or monkeys (Parker, et al., Human Gene Therapy 6: 575-590(1995); and San, et al., Human Gene Therapy 4: 781-788 (1993)). Thus, anon-viral vector is safer and can be repeatedly injected.

The present invention is further directed to compositions, and methodsfor using such compositions, for improving the effectiveness ofpolypeptide delivery into a vertebrate by administering in vivo, apolypeptide-encoding polynucleotide in an aqueous solution sodiumphosphate. The polynucleotide is incorporated into the cells of thevertebrate in vivo, and encodes a detectable amount or aprophylactically or therapeutically effective amount, of a desiredpolypeptide.

The present invention further provides a composition selected from thegroup consisting of (a) a composition comprising about 1 ng to about 30mg of a polynucleotide in aqueous solution, where the polynucleotideoperably encodes a polypeptide within vertebrate cells in vivo; andsodium phosphate dissolved in the aqueous solution at a molarconcentration from about 20 mM to about 300 mM, and reaction,association, or dissociation products thereof; and (b) a compositioncomprising: about 1 ng to about 30 mg of a polynucleotide in aqueoussolution, where the polynucleotide operably encodes a polypeptide withinvertebrate cells in vivo; sodium phosphate dissolved in the aqueoussolution at a molar concentration from about 0.1 mM to about 150 mM, andreaction, association, or dissociation products thereof; and a cationiclipid suspended in said aqueous solution; where the aqueous solution issubstantially free of chloride anion.

Another aspect of the present invention is a method for delivering apolypeptide into a vertebrate, comprising administering to thevertebrate a composition selected from the group consisting of (a) acomposition comprising about 1 ng to about 30 mg of a polynucleotide inaqueous solution, where the polynucleotide operably encodes apolypeptide within vertebrate cells in vivo; and sodium phosphatedissolved in the aqueous solution at a molar concentration from about 20mM to about 300 mM, and reaction, association, or dissociation productsthereof; and (b) a composition comprising: about 1 ng to about 30 mg ofa polynucleotide in aqueous solution, where the polynucleotide operablyencodes a polypeptide within vertebrate cells in vivo; sodium phosphatedissolved in the aqueous solution at a molar concentration from about0.1 mM to about 150 mM, and reaction, association, or dissociationproducts thereof; and a cationic lipid suspended in said aqueoussolution; where the aqueous solution is substantially free of chlorideanion; such that the polypeptide encoded by the delivered polynucleotideis expressed in the vertebrate, in an amount sufficient to bedetectable.

Another aspect of the present invention is a method for delivering atherapeutic polypeptide into a vertebrate, comprising administering to avertebrate in need of such a therapeutic polypeptide a compositionselected from the group consisting of (a) a composition comprising about1 ng to about 30 mg of a polynucleotide in aqueous solution, where thepolynucleotide operably encodes a polypeptide within vertebrate cells invivo; and sodium phosphate dissolved in the aqueous solution at a molarconcentration from about 20 mM to about 300 mM, and reaction,association, or dissociation products thereof; and (b) a compositioncomprising: about 1 ng to about 30 mg of a polynucleotide in aqueoussolution, where the polynucleotide operably encodes a polypeptide withinvertebrate cells in vivo; sodium phosphate dissolved in the aqueoussolution at a molar concentration from about 0.1 mM to about 150 mM, andreaction, association, or dissociation products thereof; and a cationiclipid suspended in said aqueous solution; where the aqueous solution issubstantially free of chloride anion; such that a therapeuticpolypeptide encoded by the delivered polynucleotide is expressed in thevertebrate, in a therapeutically effective amount.

The present invention also provides a method of producing antibodies toa polypeptide in a vertebrate, comprising administering to thevertebrate a composition selected from the group consisting of (a) acomposition comprising about 1 ng to about 30 mg of a polynucleotide inaqueous solution, where the polynucleotide operably encodes apolypeptide within vertebrate cells in vivo; and sodium phosphatedissolved in the aqueous solution at a molar concentration from about 20mM to about 300 mM, and reaction, association, or dissociation productsthereof; and (b) a composition comprising: about 1 ng to about 30 mg ofa polynucleotide in aqueous solution, where the polynucleotide operablyencodes a polypeptide within vertebrate cells in vivo; sodium phosphatedissolved in the aqueous solution at a molar concentration from about0.1 mM to about 150 mM, and reaction, association, or dissociationproducts thereof; and a cationic lipid suspended in said aqueoussolution; where the aqueous solution is substantially free of chlorideanion; such that a polypeptide encoded by the delivered polynucleotideis expressed in the vertebrate, in a sufficient amount to generateantibody to the encoded polypeptide in the vertebrate.

The present invention also provides a method of enhancing or modulatingan immune response in a vertebrate in need of such an enhanced ormodulated immune response, comprising administering to the vertebrate acomposition selected from the group consisting of (a) a compositioncomprising about 1 ng to about 30 mg of a polynucleotide in aqueoussolution, where the polynucleotide operably encodes a polypeptide withinvertebrate cells in vivo; and sodium phosphate dissolved in the aqueoussolution at a molar concentration from about 20 mM to about 300 mM, andreaction, association, or dissociation products thereof; and (b) acomposition comprising: about 1 ng to about 30 mg of a polynucleotide inaqueous solution, where the polynucleotide operably encodes apolypeptide within vertebrate cells in vivo; sodium phosphate dissolvedin the aqueous solution at a molar concentration from about 0.1 mM toabout 150 mM, and reaction, association, or dissociation productsthereof; and a cationic lipid suspended in said aqueous solution; wherethe aqueous solution is substantially free of chloride anion; such thatan immunogenic and/or immunomodulatory polypeptide encoded by thedelivered polynucleotide is expressed in the vertebrate, in a sufficientamount to induce a desired immune response in the vertebrate to preventdisease or treat disease, i.e., cure disease, reduce the severity ofdisease symptoms, or prolong the life of the vertebrate.

The invention further provides a method of delivering a physiologicallyor metabolically necessary polypeptide to a vertebrate incapable ofmaking a functional form of the polypeptide, comprising administering tothe vertebrate a composition selected from the group consisting of (a) acomposition comprising about 1 ng to about 30 mg of a polynucleotide inaqueous solution, where the polynucleotide operably encodes apolypeptide within vertebrate cells in vivo; and sodium phosphatedissolved in the aqueous solution at a molar concentration from about 20mM to about 300 mM, and reaction, association, or dissociation productsthereof; and (b) a composition comprising: about 1 ng to about 30 mg ofa polynucleotide in aqueous solution, where the polynucleotide operablyencodes a polypeptide within vertebrate cells in vivo; sodium phosphatedissolved in the aqueous solution at a molar concentration from about0.1 mM to about 150 mM, and reaction, association, or dissociationproducts thereof; and a cationic lipid suspended in said aqueoussolution; where the aqueous solution is substantially free of chlorideanion; such that a functional self polypeptide, i.e., a physiologicallyor metabolically necessary polypeptide encoded by the deliveredpolynucleotide is expressed in the vertebrate, in a sufficient amount tosupply the vertebrate's requirements for the polypeptides.

The present invention also provides a pharmaceutical kit selected fromthe group consisting of: (a) a pharmaceutical kit comprising: acontainer or containers holding about 1 ng to about 30 mg of apolynucleotide which operably encodes a polypeptide within vertebratecells in vivo; an amount of sodium phosphate which, when dissolved in aprescribed volume of distilled water, results in an aqueous solutionwith a molar concentration of sodium phosphate from about 20 mM to about300 mM, and reaction, association, or dissociation products thereof; andoptionally, an administration means and/or an instruction sheet; wherebythe polynucleotide is provided in a prophylactically or therapeuticallyeffective amount to treat a vertebrate; and (b) a pharmaceutical kitcomprising: a container or containers holding about 1 ng to about 30 mgof a polynucleotide which operably encodes a polypeptide withinvertebrate cells in vivo; an amount of sodium phosphate which, whendissolved in a prescribed volume of distilled water, results in anaqueous solution with a molar concentration of said salt from about 0.1mM to about 150 mM, and reaction, association, or dissociation productsthereof, and where the aqueous solution formed thereby is essentiallyfree of chloride anion; a cationic lipid; and optionally, anadministration means and/or an instruction sheet; whereby thepolynucleotide is provided in a prophylactically or therapeuticallyeffective amount. Any of components of the pharmaceutical kit can beprovided in a single container, or in multiple containers packagedtogether.

The inventors have discovered that delivery of the compositions providedherein to a vertebrate results in much improved in vivo polypeptideexpression over the delivery of existing nucleic acid-basedcompositions, e.g., compositions comprising polynucleotides which encodea polypeptide and an aqueous solution consisting of sterile water,normal saline (i.e., 154 mM sodium chloride), or phosphate bufferedsaline (i.e., 154 mM sodium chloride plus 10 mM sodium phosphate).

BRIEF DESCRIPTION OF THE FIGURES

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same become betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying figures.

FIG. 1 shows the plasmid map of VR4151 (SEQ ID No. 4). Thecytomegalovirus immediate-early gene promoter enhancer and 5′untranslated sequences (5′UTR+intron A) drive the expression of thehuman interferon ω coding sequence. The transcriptional terminatorregion includes polyadenylation and termination signals derived from therabbit β-globin gene.

FIGS. 2A and 2B show the pharmacokinetics of hIFNω in the serum ofC57BL/6 mice (FIG. 2A) and nude mice (FIG. 2B) after a singleintramuscular (i.m.) injection of hIFNω plasmid DNA (VR4151). Mice wereinjected i.m. with 100 μg of VR4151. Following the intramuscularinjection, mice were bled daily, and serum was collected and assayed forhIFNω polypeptide using an ELISA. Each point represents an average offour mice. In C57BL/6 mice, the single i.m. injection resulted in peakserum levels of 254 pg/ml on day 6 after injection, and serum levelswere still detectable 14 days after injection (50 pg/ml) (FIG. 2A). Innude mice, the single i.m. injection resulted in peak serum levels of648 pg/ml on day 7, and serum levels were still detectable 14 days afterinjection (134 pg/ml) (FIG. 2B).

FIGS. 3A-3F show that systemic mIFNα treatment reduces tumor volume(FIGS. 3A, 3C, and 3E) and increases survival (FIGS. 3B, 3D, and 3F) inthree murine tumor models. C57BL/6 mice bearing subcutaneous B16F10melanoma (FIGS. 3A and 3B), subcutaneous glioma 261 (FIGS. 3C and 3D),or DBA/2 mice bearing subcutaneous Cloudman melanoma (FIGS. 3E and 3F)were injected with 100 μg either of VR4111 (mIFNα plasmid) or VR1055(control plasmid), twice per week for three weeks, beginning on day 4after tumor cell injection (n=8-10 mice per group).

FIGS. 4A and 4B show that systemic mIFNα, mIL-2 or mIL-12 plasmid DNAtreatment reduces tumor volume (FIG. 4A) and mIFNα or mIL-12 plasmid DNAtreatment increases survival (FIG. 4B) in the subcutaneous B16F10melanoma model. C57BL/6 mice bearing subcutaneous B16F10 melanoma wereinjected with 100 μg of VR4111 (mIFNα), VR4001 (mIL-12), VR1110 (mIL-2),or VR1012 (control plasmid) (n=15-16 mice per group) twice per week forthree weeks.

FIGS. 5A and 5B show that i.m. administration of hIFNω pDNA reducestumor volume (FIG. 5A) and increases survival (FIG. 5B) in nude micebearing human A431 epidermoid carcinoma tumors. Mice bearing human A431tumors between 30-80 mm³ were injected i.m. with 200 μg of either VR4151(hIFNω plasmid) or VR1055 (control plasmid) twice per week for threeweeks (n=15)

FIG. 6 shows that i.m. administration of mIFNα pDNA reduces B16F10melanoma lung metastases in C57BL/6 mice. Mice bearing lung metastasesof B16F10 melanoma were injected i.m. with 100 μg of either VR4111 orVR1055 twice per week for three weeks, beginning on day 4 after tumorcell injection (n=10 mice per group). “TNTC” means too numerous to countas seen in the control group.

FIGS. 7A and 7B show that i.m. administration of mIFNα pDNA reducesintradermal M5076 primary tumor growth (FIG. 7A) as well as livermetastases (FIG. 7B) in C57BL/6 mice bearing murine M5076 reticulum cellsarcoma cells. Mice bearing M5076 tumors were injected i.m. with 100 μgof either VR4111 or VR1055 twice per week for three weeks, beginning onday 4 after tumor cell inoculation (n=10-13 mice per group).

FIGS. 8A-8D show a comparison of different dosages and frequencies ofmIFNα pDNA administration in the subcutaneous B16F10 melanoma model.C57BL/6 mice bearing subcutaneous B16F10 melanoma were injected i.m.with 50 μg or 100 μg of either VR4111 or VR1055 twice a week for 3 weeksbeginning 4 days after tumor cell inoculation (n=10 mice per group). Allgroups treated with 100 μg of VR4111 showed significant reduction intumor growth by day 21 (p=0.002) and significant enhancement in survival(p<0.008) with all treatments tested (FIGS. 8A and 8B). In mice treatedwith 50 μg VR4111, tumor growth was significantly reduced by day 21(p=0.005), and survival was significantly increased (p<0.003) in thegroups of mice that were injected twice per week or once per week. Thegroup injected every other week with 50 μg VR4111 was not significantlydifferent from the mice that received the control plasmid (FIGS. 8C and8D).

FIGS. 9A-9D shows the results of experiments performed to determine therole of NK and T cells in the antitumor response induced by mIFNαplasmid DNA. Nude mice (T cell deficient) (FIGS. 9A and 9B), andbeige-nude mice (NK and T cell deficient) (FIGS. 9C and 9D) bearingsubcutaneous B16F10 melanoma tumors were injected i.m. with 100 μg ofeither VR4111 or VR1055 twice per week for three weeks, beginning on day4 after tumor cell injection (n=15 mice per group). No significantreduction in tumor volume or increase in survival was found for nude ornude-beige mice treated with VR4111, suggesting that T cells areinvolved in the mIFNα antitumor response.

FIGS. 10A and 10B show the results of experiments performed to evaluatethe role of CD4⁺ and CD8⁺ T cells in the mIFNα DNA antitumor response.For depletion of CD4⁺ and CD8⁺ T cells, C57BL/6 mice bearingsubcutaneous B16F1 melanoma tumors were injected i.p. with 500 μg ofeither the anti-CD4 mAb (clone GK1.5, rat IgG) (ATCC, Rockville, Md.) oranti-CD8 mAb (clone 2.43, rat IgG) (ATCC, Rockville, Md.) one day aftereach i.m. injection of 100 μg of either VR4111 or VR1055 twice per weekfor three weeks (n=10 mice per group). The mIFNα plasmid DNA therapysignificantly reduced tumor growth (p≦0.002) and enhanced survival(p≦0.008) of both normal mice and mice depleted of CD4⁺ T cells,suggesting that CD4⁺ T cells were not required for the response. Incontrast, mice depleted of CD8⁺ T cells and injected with VR4111 hadtumor volumes and survival that were not significantly different frommice treated with the control plasmid DNA, indicating a requirement forCD8⁺ T cells in the antitumor response.

FIGS. 11A and 11B show that intratumoral hIFNω (VR4151) and hIFNα(VR4112) treatment reduces tumor volume in the human A375 melanoma model(FIG. 11A) and human NIH-OVCAR3 (FIG. 11B) in nude mice. Mice bearingsubcutaneous tumor received direct intratumoral injections of a complexof DNA:DMRIE/DOPE (1:1 DNA:lipid mass ratio, 100 μg of plasmid DNA) for6 consecutive days followed by an additional 5 treatments every otherday for a total of 11 injections (A375 melanoma model), or for everyother day for a total of 11 injections (NIH-OVCAR3 ovarian cancermodel).

FIGS. 12A and 12B show that intratumoral mIFNα (VR4101) plasmid DNAtreatment reduces tumor volume (FIG. 12A) and increases survival (FIG.12B) in the subcutaneous B16F10 melanoma model in C57BL/6 mice. Micereceived a subcutaneous implantation of 10⁴ B16F10 cells into the flank.Beginning at day 12 post tumor implant, mice received six consecutiveintratumoral injections of a complex of pDNA:DMRIE/DOPE (1:1 DNA:DMRIEmass ratio 100 μg of plasmid DNA).

FIGS. 13A and 13B show luciferase activity in peritoneal tissues and MOTascites in mice after i.p. injection of luciferase DNA:lipid complex.The results show high levels of reporter gene expression in ascites butlow levels in peritoneal tissue. MOT tumor-bearing C3H/HeN mice receivedi.p. injections of a complex of pDNA:DMRIE/DOPE (1:1 DNA:DMRIE massratio, 100 μg of plasmid DNA) on days 5 and 6 after tumor cell implant.Tissues were collected 1 day (FIG. 13A) or 3 days (FIG. 13B) followingthe DNA:lipid injection.

FIGS. 14A and 14B show serum levels of IL-2 after i.p. injection ofeither IL-2 pDNA or protein in MOT tumor bearing mice. The serum levelsof IL-2 were much lower than levels in ascites. Ascites and serum werecollected at 4 hours and days 1, 2, 3, 6 and 10 post DNA or proteininjection (5 mice for each time point), and analyzed for mIL-2polypeptide using an ELISA.

FIGS. 15A-15F show a significant reduction in MOT tumor growth (p=0.01)(FIG. 15A) and increased survival (p=0.04) (FIG. 15B) of mice treatedwith i.p. injection of IL-2 pDNA:lipid on days 5-10 after tumor cellinjection. The DNA was complexed at either a 1:1 (15A and 15B) or 5:1(FIGS. 15C and 15D) DNA:DMRIE mass ratio (100 μg pDNA). Plasmid DNAwithout lipid was not effective (FIGS. 15E and 15F)

FIGS. 16A and 16B show, that i.p. mIL-2 plasmid DNA (VR1110):lipidtreatment inhibits tumor growth (FIG. 16A) and enhances survival (FIG.16B) in the MOT tumor model in C3H/HeN mice. MOT tumor-bearing micereceived three alternative-day i.p. injections of a complex ofpDNA:DMRIE/DOPE (1:1 DNA:DMRIE mass ratio, 100 μg of plasmid DNA).

FIGS. 17A and 17B show a significant reduction in MOT tumor growth andincreased survival of mice treated with i.p. injection of IL-2 DNA:lipidfollowed by debulking of tumor ascites. MOT tumor-bearing mice receivedsix consecutive intraperitoneal injections of a complex ofpDNA:DMRIE/DOPE (1:1 DNA:DMRIE mass ratio, 100 μg of pDNA) and debulkedof 5 ml of tumor ascites 4 days after the last DNA:lipid injection(n=10).

FIGS. 18A and 18B show dose-response of mIL-2 pDNA (VR110):lipidtreatment in the MOT tumor model. C3H/HeN mice bearing MOT tumor wereinjected with 25, 50 or 100 μg of VR1110:DMRIE/DOPE on days 5, 8 and 11after MOT tumor cell injection. In mice treated with 50 or 100 μg ofVR1110, tumor growth was significantly reduced (p=0.002) and survivalsignificantly enhanced (p=0.01) by day 15 post tumor cell inoculationcompared to the control. Tumor-bearing mice treated with 25 μg ofVR1110:lipid were not significantly different from the control mice foreither tumor volume or survival (n=15).

FIGS. 19A-19D show the cytokine profile of ovarian tumor ascites inC3H/HeN mice MOT tumor model following mIL-2 pDNA (VR1110):lipidtreatment. Mice received i.p. injections of a complex of pDNA/DMRIE/DOPE(1:1 DNA/DMRIE mass ratio, 100 μg of plasmid DNA) on days 5, 8 and 11after tumor cell implant. Two days after each injection, mice weresacrificed (5 mice for each time point), and the ascites were collectedand analyzed for cytokine concentration. The level of IL-2 (days 7, 10and 13) as well as IFNγ and GM-CSF (days 10 and 13) were markedlyelevated suggesting that IL-2 upregulates IFNγ and GM-CSF production.

FIGS. 20A and 20B show that i.p. mIFNα pDNA (VR4111):lipid treatmentenhances survival (FIG. 20B) in the MOT tumor model in C3H/HeN mice. MOTtumor-bearing mice received three alternative-day i.p. injections of acomplex of pDNA:DMRIE/DOPE (1:1 DNA:DMRIE mass ratio, 100 μg of plasmidDNA).

FIG. 21 shows the schematic contents of plasmid DNAs used in theexamples that follow. All vectors contain a pUC19 origin of replication,human cytomegalovirus intron A, and the bacterial kanamycin resistancegene. “Lux” denotes the coding region encoding luciferase, from thefirefly, Photinus pyralis; “CMV” denotes the human cytomegalovirusimmediate early region—promoter and enhancer; “BGH” denotes the bovinegrowth hormone transcriptional terminator; “LacZ” denotes the codingregion encoding the β-galactosidase protein of Escherichia coli; “RSV”denotes the Rous sarcoma virus promoter and enhancer; “EPO” denotes thecoding region encoding murine erythropoietin; “SEAP” denotes the codingregion for secreted human placental alkaline phosphatase; “Ratpreproinsulin” denotes the coding region for rat preproinsulincontaining a point mutation to change histidine B10 (codon CAC), toaspartic acid (codon GAC), Abai, A. M., et al. Human Gene Therapy10:2637-2649 (1999); “IFN-omega” denotes the coding region encodinghuman interferon-ω; “mRGB” denotes the modified rabbit β-globintranscriptional terminator; and “NP” denotes the coding region encodingthe nucleoprotein of influenza virus A/PR/8/34. Intermediate andparental plasmids *VR1012, **VR1255 and ***VIJ were prepared asdescribed by Manthorpe, M. et al., Hum. Gene Ther. 4:419-431 (1993),Hartikka, J. et al., Hum. Gen. Ther. 7:1205-1217 (1996), and Montgomery,D. L. et al., DNA Cell Biol. 12:777-783 (1993), respectively. VR1043 wasderived from VR1012 by replacing the SacI-NdeI CMV promoter enhancerfragment with the RSV promoter enhancer.

FIG. 22A is a bar graph demonstrating the effectiveness of sodiumphosphate concentration on luciferase expression in mouse muscle. Fiftyμg of plasmid VR1223 DNA per 50 μl sodium phosphate solution at theindicated molar concentrations was injected into mouse quadriceps andthe muscles were extracted and assayed for enzyme activity 7 days later.Bars represent Standard Error of the Mean (n=50, 5 experiments each withn=10 per concentration). Peak expression occurred with DNA dissolved in150 mM sodium phosphate, and yielded 386 ng luciferase per muscle whichis 4.3-fold higher than the saline average (dashed line at 89 ngluciferase per muscle). The 80, 100, 150 and 200 mM sodium phosphatevalues were significantly higher than saline by Mann-Whitney rank sumtest (p<0.05).

FIG. 22B is a bar graph demonstrating the effect of pH of the sodiumphosphate and potassium phosphate solutions on luciferase expression inmouse muscle. Fifty μg of plasmid VR1223 DNA per 50 μl sodium phosphateand potassium phosphate solution at the indicated pH was injected intomouse quadriceps and the muscles were extracted and assayed for enzymeactivity 7 days later. Bars represent Standard Error of the Mean (n=20muscles per group).

FIG. 22C is a graph plotting the effect of pH of the various saltsolutions listed in Table 11-A on luciferase expression in mouse muscle.

FIG. 22D is a graph plotting the effect of osmolarity of the varioussalt solutions listed in Table 11-B on luciferase expression in mousemuscle.

FIG. 23 is a bar graph demonstrating the reproducibility of theenhancement of luciferase expression in muscle upon delivery in 150 mMsodium phosphate. In each of nine experiments, ten quadriceps muscles in5 mice per group were injected with 50 μg of plasmid VR1223 DNAdissolved in 50 μl saline or in 150 mM sodium phosphate (NaP). Barsrepresent the average ng luciferase per muscle for each experimentnumbered 1 through 9. Error bars represent Standard Error of the Mean.

FIG. 24 shows the comparison of the effect of a 150 mM sodium phosphatesolution on the expression of three reporter genes. Fifty μg of plasmidVR1223 (luciferase), 10 μg of plasmid VR1418 (β-galactosidase, or LacZ)or 50 μg of plasmid VR4151 (human IFNω) dissolved in 50 μl saline or in150 mM sodium phosphate solution were injected into the quadricepsmuscles of BALB/c mice. For luciferase and LacZ DNAs, the muscles wereextracted and assayed 7 days later for enzyme activity. For IFN-ω DNA,serum was collected at 7 days after the injection and assayed for IFN-ωprotein. Values are expressed as average ng of gene product per muscleor per ml serum. Bars represent Standard Error of the Mean. Forluciferase, n_(Saline)=413, n_(NaP)=120; for β-galactosidase,n_(Saline)=119, n_(NaP)=180; for IFN-ω, n_(Saline)=10, n_(NaP)=9. Theaverage expression in NaP was significantly higher than saline byMann-Whitney rank sum test for luciferase (p=0.001), β-galactosidase(p=0.001) and IFNω (p=0.02).

FIG. 25 shows long-term effects of a 150 mM sodium phosphate solution onthe expression of secreted reporter gene products. Compositionscomprising plasmids VR3301 encoding human placental alkaline phosphatase(SEAP), VR3502 encoding rat preproinsulin, and VR2901 encoding mouseerythropoietin, dissolved in saline or in 150 mM sodium phosphate, wereinjected bilaterally into mice as described in Example 1. At theindicated times after injections, serum was collected and assayed forSEAP or proinsulin expression, or hematocrits were measured as anindication of erythropoietin expression. Control mice injected withplasmid DNA encoding canine clotting Factor IX (open triangles in thelower graph) in 150 mM sodium phosphate exhibited an average hematocritof 46. Bars represent Standard Error of the Mean (n=10). By theMann-Whitney rank sum test, the sodium phosphate values weresignificantly different (p values all <0.007) from the saline values foreach time point and for all three reporters.

FIG. 26 shows the effect of a 150 mM sodium phosphate solution on DNAdegradation in mouse muscle extract or serum. VR1255 plasmid DNAdissolved in each of 4 aqueous solutions was spiked with 10% (v/v)unbuffered mouse Muscle Extract or Serum and the spiked solutions wereincubated for 2 hours at 37° C. The reactions were neutralized withSDS+EDTA and analyzed by agarose gel electrophoresis. The top row offour lanes are from the solutions spiked with muscle extract and thebottom row of lanes are from the solutions spiked with serum. The DNAsamples from left to right are in: Control solution (pre-neutralizedsample in water), Water, Saline, or NaP (150 mM sodium phosphate). Onthe right side of the right lane are indicated the position of the bandscorresponding to nicked, linear, closed circular, and degraded plasmidDNA. The numbers at the bottom of the lower lanes are 7 day luciferaseexpression values taken from Tables 1 and 2 where DNA in the indicatedvehicle was injected into muscle.

FIGS. 27A and 27B show the effects of a 150 mM sodium phosphate solutionon DNA vaccination. Mice were vaccinated bilaterally in the quadricepsmuscle with 5 μg of plasmid VR4700, encoding the influenza virusnucleoprotein, which was dissolved in 50 μl of saline or in 50 μl of 150mM sodium phosphate on days 0 and 21. (A) Serum was collected at day 42and assayed for anti-NP antibody titer by ELISA. Three separateexperiments were performed with n=10 mice each, labeled 1-3. The average(Avg.) of all three experiments is indicated in the black bar. Valuesare expressed as anti-NP specific titer (n=10, 2 experiments with n=5).Error bars represent Standard Error of the Mean. Average anti-NP titersfrom NaP groups 1-3 were significantly different from the salineaverages by Mann-Whitney rank sum test (p<0.04) as was the averagetiters from all 3 groups (p<0.001). (B) At day 60 the spleens werecollected, dissociated and assayed for the presence of NP-specificcytolytic T lymphocyte activity. Splenocytes from unvaccinated miceserved as controls (“Naïve”). Average % NP specific lysis from thesaline and NaP groups were not significantly different by Mann Whitneyrank sum test.

FIG. 28 shows the effects of sodium phosphate solutions on luciferaseexpression in lung following delivery of compositions comprising plasmidDNA encoding luciferase. Mouse lungs were intranasally instilled withcompositions comprising 132 μg of plasmid VR1223 encoding luciferase,complexed with GAP-DLRIE/DOPE (1:1) cationic liposomes at a molar ratioof 4:1 DNA to lipid in water or in various aqueous solutions of sodiumphosphate. The lungs were extracted 3 days later and assayed forluciferase activity. Values are expressed in ng luciferase per lung +/−Standard Error of the Mean (n_(water) and n_(25mMNaP)=35; n_(10mMNaP),and n_(150mMNap)=15 with n=5 per each individual experiment). The 2.5 mMNaP solution averages were significantly different by Mann-Whitney ranksum test from all the other groups (p=<0.001).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is broadly directed to treatment of cancer byadministering in vivo, into a tissue of a mammal suffering from cancer,at least one polynucleotide construct comprising at least onepolynucleotide encoding at least one cytokine, or at least one activefragment thereof. The polynucleotide construct is incorporated into thecells of the mammal in vivo, and a therapeutically effective amount of acytokine is produced in vivo, and delivered to tumor cells. Combinationsof cytokine-encoding polynucleotides can be administered.

The present invention provides a pharmaceutical composition comprisingabout 1 ng to 20 mg of a non-infectious, non-integrating polynucleotideconstruct comprising a polynucleotide selected from the group consistingof (a) a polynucleotide that hybridizes under stringent conditions tothe nucleotide sequence of SEQ ID No. 7 or the complement thereof,wherein the polynucleotide sequence encodes a polypeptide that hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; (b)a polynucleotide that encodes a polypeptide comprising an amino acidsequence which, except for at least one but not more than 20 amino acidsubstitutions, deletions, or insertions, is identical to amino acids −23to 172 or 1 to 172 in SEQ ID No. 8, and wherein the polypeptide hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; and(c) a polynucleotide that encodes a polypeptide comprising amino acids86-172 in SEQ ID No. 8, wherein the polypeptide has antiproliferativeactivity when added to NIH-OVCAR3 cells in vitro; and one or morecationic compounds selected from the group consisting of cationiclipids, cationic peptides, cationic proteins, cationic polymers, andmixtures thereof. The pharmaceutical composition can be used to practiceall of the methods of the present invention.

The present invention also provides a pharmaceutical compositionobtained by complexing a polynucleotide selected from the groupconsisting of (a) a polynucleotide that hybridizes under stringentconditions to the nucleotide sequence of SEQ ID No. 7 or the complementthereof, wherein the polynucleotide sequence encodes a polypeptide thathas antiproliferative activity when added to NIH-OVCAR3 cells in vitro;(b) a polynucleotide that encodes a polypeptide comprising an amino acidsequence which, except for at least one but not more than 20 amino acidsubstitutions, deletions, or insertions, is identical to amino acids −23to 172 or 1 to 172 in SEQ ID No. 8, wherein the polypeptide hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; and(c) a polynucleotide that encodes a polypeptide comprising amino acids86-172 in SEQ ID No. 8, wherein the polypeptide has antiproliferativeactivity when added to NIH-OVCAR3 cells in vitro, with one or morecationic compounds selected from the group consisting of cationiclipids, cationic peptides, cationic proteins, cationic polymers, andmixtures thereof.

The pharmaceutical composition of the present invention can be apolynucleotide construct comprising a polynucleotide that hybridizesunder stringent conditions to the nucleotide sequence of SEQ ID No. 7 orthe complement thereof, wherein the polynucleotide sequence encodes apolypeptide that has antiproliferative activity when added to NIH-OVCAR3cells in vitro, and one or more cationic compounds selected from thegroup consisting of cationic lipids, cationic peptides, cationicproteins, cationic polymers, and mixtures thereof. Alternatively, thepharmaceutical composition of the present invention can be apolynucleotide construct comprising a polynucleotide that encodes apolypeptide comprising an amino acid sequence which, except for at leastone but not more than 20 amino acid substitutions, deletions, orinsertions, is identical to amino acids −23 to 172 or 1 to 172 in SEQ IDNo. 8, wherein the polypeptide has antiproliferative activity when addedto NIH-OVCAR3 cells in vitro, and one or more cationic compoundsselected from the group consisting of cationic lipids, cationicpeptides, cationic proteins, cationic polymers, and mixtures thereof.Alternatively, the pharmaceutical composition of the present inventioncan be a polynucleotide construct comprising a polynucleotide thatencodes a polypeptide comprising amino acids 86-172 in SEQ ID No. 8,wherein the polypeptide has antiproliferative activity when added toNIH-OVCAR3 cells in vitro; and one or more cationic compounds selectedfrom the group consisting of cationic lipids, cationic peptides,cationic proteins, cationic polymers, and mixtures thereof.

The pharmaceutical composition of the present invention comprises atleast one polynucleotide construct comprising at least onepolynucleotide encoding an IFNω, or an active fragment thereof.Preferably, the polynucleotide construct contains a polynucleotideencoding a human IFNω. More preferably, IFNω is encoded by nucleotides 1to 585 in SEQ ID No. 7 (corresponding to amino acids −23 to 172 in SEQID No. 8), or by nucleotides 70 to 585 in SEQ ID No. 7 (corresponding toamino acids 1 to 172 in SEQ ID No. 8). Most preferably, thepolynucleotide construct is VR4151 in SEQ ID No. 4. The polynucleotideconstruct may be complexed with one or more cationic compounds selectedfrom the group consisting of cationic lipids, cationic peptides,cationic proteins, cationic polymers, and mixtures thereof. Preferably,the polynucleotide construct is complexed with one or more cationiclipids. More preferably, the polynucleotide construct is complexed withone or more cationic lipids and one or more neutral lipids. Still morepreferably, the cationic lipid is(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propaniminiumbromide (DMRIE) and the neutral lipid is1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) such that themass ratio of polynucleotide construct to lipid is from about 10:1 andabout 0.5:1. More preferably, the mass ratio of polynucleotide constructto lipid is from about 5:1 and about 1:1. Still more preferably, themass ratio of polynucleotide construct to lipid is about 5:1.

Cytokine-encoding plasmids discussed herein include VR4102 (hIFNα in theVR1012 vector) (SEQ ID No. 1), VR4112 (hIFNα in the VR1055 vector) (SEQID No. 2), VR4150 (hIFNω in the VR1012 vector) (SEQ ID No. 3), VR4151(hIFNω in the VR1055 vector) (SEQ ID No. 4), VR4101 (mIFNα in the VR1012vector) (SEQ ID No. 5), VR4111 (mIFNα in the VR1055 vector) (SEQ ID No.6), and VR1110 (mIL-2 in the VR1012 vector), VR1103 (hIL-2 in the VR1012vector) (SEQ ID No: 25), VR4001 (mIL-12 in the VR1033 vector), andVR1700 (mGM-CSF in the VR1012 vector).

Cytokine-encoding cDNAs discussed herein include the cDNA for hIFNω (SEQID No. 7), the cDNA for hIFNα (SEQ ID No. 9), the cDNA for mIFNα (SEQ IDNo. 11), the cDNA for hIL-2 (SEQ ID No. 13 and the coding portion of SEQID No. 25), the cDNA for mIL-2 (for example, as disclosed in Kashima etal., Nature 313:402-404 (1985), which is hereby incorporated byreference) the cDNA for mIL-12 (for example, as disclosed in Tone etal., Eur. J. Immunol. 26:1222-1227(1996), which is hereby incorporatedby reference), and the cDNA for mGM-CSF (for example, as disclosed inGough et al., EMBO J. 4:645-653 (1985), which is hereby incorporated byreference). Cytokine polypeptides discussed herein include hIFNω (SEQ IDNo. 8), hIFNα (SEQ ID No. 10), mIFNα (SEQ ID No. 12), and hIL-2 (SEQ IDNo. 14 and SEQ ID No. 26).

By “stringent conditions” is intended a hybridization by overnightincubation at 42° C. in a solution comprising: 50% formamide, 5×SSC (750mM NaCl, 15 mM trisodium citrate), 50 mM sodium phosphate (pH 7.6), 5×Denhardt's solution, 10% dextran sulfate, and 20 μg/ml denatured,sheared salmon sperm DNA, followed by repeatedly washing the filters (atleast three times) in 0.1×SSC and 0.1% sodium dodecyl sulfate (w/v) for20 minutes at about 65° C.

By “active fragment” is intended a fragment of a cytokine that displaysthe antiproliferative activity of the mature or full length cytokine.For example, a full length hIFNω is set forth in amino acids −23 to 172of SEQ ID No. 8. The corresponding mature hIFNω is set forth in aminoacids 1 to 172 of SEQ ID No. 8. Active fragments of hIFNω include, butare not limited to a polypeptide comprising amino acids 86-172 in SEQ IDNo. 8, a polypeptide comprising amino acids 61-172 in SEQ ID No. 8, apolypeptide comprising amino acids 41-172 in SEQ ID No. 8, and apolypeptide comprising amino acids 21-172 in SEQ ID No. 8. A full lengthhIFNα is set forth in amino acids −23 to 166 of SEQ ID No. 10. Thecorresponding mature hIFNα is set forth in amino acids 1 to 166 of SEQID No. 10. Active fragments of hIFNα include, but are not limited to apolypeptide comprising amino acids 83-166 in SEQ ID No. 10, apolypeptide comprising amino acids 61-166 in SEQ ID No. 10, apolypeptide comprising amino acids 41-166 in SEQ ID No. 10, and apolypeptide comprising amino acids 21-166 in SEQ ID No. 10. Full lengthhIL-2 is set forth in amino acids −20 to 133 of SEQ ID No. 14. Thecorresponding mature hIL-2 is set forth in amino acids 1 to 133 of SEQID No. 14. Active fragments of hIL-2 include, but are not limited to apolypeptide comprising amino acids 58 to 105 in SEQ ID No. 14, and apolypeptide comprising amino acids 20 to 126 in SEQ ID No. 14.

Assays of antiproliferative activity in vitro are well known to those ofordinary skill in the art. For example, one antiproliferation assay thatcan be used is to treat cultured cells, such as human ovarian NIH-OVCAR3cells (ATCC, Rockville, Md.), with supernatants from human melanomaUM449 cells transfected with the polynucleotide construct containing apolynucleotide encoding an IFNω or an active fragment thereof. In thisantiproliferation assay, NIH-OVCAR3 cells are cultured and plated in 96well-tissue culture plates. The plates are incubated for 24 hours at 37°C. in a humidified 5% CO₂ atmosphere. Twenty μl of tissue culturesupernatants from transfected UM449 cells are added to duplicate wells.An interferon reference standard (e.g., human leukocyte interferon,Sigma Chemical Co., St. Louis, Mo.) is included in each assay. The cellsare incubated with the test samples or the interferon standard for anadditional 72 hours at 37° C. To quantitate the effects on cellproliferation, 50 μl of XTT/ECR substrate (Cell Proliferation Kit,Boehringer Mannheim, Indianapolis, Ind.) is added to each well and theplates are incubated for an additional 24 hours at 37° C. prior tomeasurement of the OD₄₉₀. Other cell lines can be used in theantiproliferation assay. For example, any of the cells listed on Table 1can be used. Another antiproliferation assay that can be used isprovided in Nieroda, et al (Mol. Cell. Differentiation 4: 335-351(1996)).

For treatment of cancer, a polynucleotide construct comprising apolynucleotide encoding a cytokine can be delivered locally,systemically or intra-cavity. In the “systemic delivery” embodiment ofthe invention, one or more polynucleotide construct comprising one ormore polynucleotide encoding one or more cytokine is administered into atissue such that the polynucleotide is expressed as the cytokine in vivoand the cytokine is released into the circulation, and such that atherapeutically effective amount of the cytokine is systemicallydelivered to the tumor. In this embodiment, the polynucleotide constructcan be administered within ex vivo cells or associated with ex vivocellular material. Preferably, the cytokine is an IFNω, IFNα, IFNτ,IFNγ, IFNβ, IL-1, IL-2, IL-4, IL-7, IL-12, IL-15, IL-18, GM-CSF, or anycombination of these, or any combination of one or more of these and oneor more additional cytokines. More preferably, the cytokine is an IFNα,IFNω, IL-2, or IL-12. Most preferably, the cytokine is an IFNα or IFNω.Examples of the combination are a polynucleotide encoding an IFNω and anIFNα; a polynucleotide encoding an IFNω and an IL-2; a polynucleotideencoding an IFNα and an IL-2; and a polynucleotide encoding an IFNα, anIFNα, and an IL-2. More preferably, the polynucleotide constructcontains a polynucleotide encoding an IFNω and/or an IFNα. Even morepreferably, the polynucleotide construct contains a polynucleotideencoding a human IFNω and/or a human IFNα. Even more preferably, thepolynucleotide encodes a human IFNω. Preferably, the polynucleotideconstruct is administered free from ex vivo cells and free from ex vivocellular material.

In this embodiment, administration can be into tissue including but notlimited to muscle, skin, brain, lung, liver, spleen, bone marrow,thymus, heart, lymph nodes, blood, bone, cartilage, pancreas, kidney,gall bladder, stomach, intestine, testis, ovary, uterus, rectum, nervoussystem, eye, gland, or connective tissue. Preferably, the administrationis into muscle tissue. i.e., skeletal muscle, smooth muscle, ormyocardium, and the polynucleotide construct is naked. Most preferably,the muscle is skeletal muscle. For polynucleotide constructs in whichthe polynucleotide encoding a cytokine is DNA, the DNA can be operablylinked to a cell-specific promoter that directs substantialtranscription of the DNA only in predetermined cells.

By “naked” is meant that the polynucleotide construct is free fromassociation with any delivery vehicle known in the art that can act tofacilitate entry into cells, for example, from transfection-facilitatingproteins, viral particles, liposomes, cationic lipids, and calciumphosphate precipitating agents.

As used herein, “ex vivo” cells are cells into which the polynucleotideconstruct is introduced, for example, by transfection, lipofection,electroporation, bombardment, or microinjection. The cells containingthe polynucleotide construct are then administered in vivo intomammalian tissue. Such ex vivo polynucleotide constructs are well-knownto those of ordinary skill in the art. For example, see Belldegrun, A.,e al., J. Natl. Cancer Inst. 85: 207-216 (1993); Ferrantini, M. et al.,Cancer Research 53: 1107-1112 (1993); Ferrantini, M. et al., J.Immunology 153: 4604-4615 (1994); Kaido. T., et al., Int. J. Cancer 60:221-229 (1995); Ogura, H., et al., Cancer Research 50: 5102-5106 (1990);Santodonato, L., et al., Human Gene Therapy 7:1-10 (1996); Santodonato.L., et al., Gene Therapy 4:1246-1255 (1997); and Zhang, J.-F. et al.,Cancer Gene Therapy 3: 31-38 (1996).

The polynucleotide construct is administered in a “cell-free” fashionwhen it is administered independently, i.e., free of ex vivo cells or exvivo cellular material.

In the “local cytokine delivery” embodiment of the present invention, apolynucleotide construct comprising a polynucleotide encoding IFNωand/or IFNα is administered in vivo into or near a tumor of a mammal,such that the polynucleotide is incorporated into the cells of thetumor. Tumor cells subsequently express the interferon polypeptide in anamount effective to treat cancer.

In this embodiment, a polynucleotide construct comprising apolynucleotide encoding an IFNω and/or an IFNα can be administered intothe tumor. Alternatively, the polynucleotide construct can beadministered into non-tumor cells surrounding a tumor, near a tumor, oradjacent to a tumor, such that a therapeutically effective amount of anIFNω and/or an IFNα is produced in vivo near or within the tumor and isdelivered to the malignant cells of the tumor. One way to provide localdelivery of the polynucleotide construct is by administeringintravenously a polynucleotide construct comprising a tumor-targetedpromoter, wherein the polynucleotide is incorporated into the cells ofthe tumor and the cytokine is expressed in the tumor in an amounteffective to treat cancer. Preferably, the polynucleotide construct isadministered into the tumor.

In the “intra-cavity delivery” embodiment, the present inventionprovides a method of selectively transfecting malignant cells in atumor-bearing body cavity of a mammal by introducing a polynucleotideconstruct into the body cavity, wherein the polynucleotide isincorporated into tumor cells and the tumor cells subsequently expressthe protein encoded by the polynucleotide in an amount effective totreat cancer. The polynucleotide construct is administered free from exvivo cells and free from ex vivo cellular material.

A cavity is a space within the body that can confine a fluid volume forsome period of time. The cavity can either be present in a normalanimal, or it can be produced as a result of disease, surgery or trauma.Cavities in the normal animal include the peritoneum, the cerebrospinalfluid space, the ventricles of the brain, the plural space around lung,the bronchiolar airways, the nasal sinus, the bladder, the vagina, theear, the synovium of various joints (knee, hip etc.), the internalnetwork of salivary gland tissue, and the gastrointestinal tractincluding stomach. Surgical removal of tumor tissue can also produce aspace which fits the definition of a cavity. An open wound produced bytrauma or surgery and closed by suture can be defined as a cavity, andthe area under a blister produced by an infection, abrasion or a burnalso fits the definition.

There are special bioavailability considerations when a gene deliverysystem is administered into a cavity. First the fluid volume in thecavity can be substantially comprised of the vehicle in which thedelivery system is suspended. Second, the delivery system can haveparticular access to cells that are either suspended in the cavity, orthat are lining the surface of the cavity. Third, in some cases normallydifferentiated cells that are lining the cavity may be embedded in anextracellular matrix and, may not be accessible to the delivery system.Thus, the delivery system may preferentially transfect cells that aregrowing outside the normal extracellular matrix and avoid the cells thatare growing within the extracellular matrix, conferring a kind of cellselectivity to the delivery system.

With respect to the first point, body fluids such as serum, have beenshown to inhibit gene delivery systems. For example, the transfectionactivities of Lipofectin and LipofectAMINE are inhibited by serum. It isthought that serum factors bind to cationic lipid/DNA complexes andblock their uptake into cells. In cavity models the endogenous fluidvolume can be removed, the cavity can be washed, and the delivery systemcan be administered into the cavity in a vehicle that is compatible withoptimal gene delivery efficacy. Thus the cavity model allows theinvestigator to create a fluid environment which allows for optimal genedelivery potency.

With respect to the second point, cells that are either floating in thecavity or are lining the surface of the cavity have preferential accessto the delivery system and can be preferentially transfected relative toother cells in the body. Since the delivery system is confined withinthe cavity, peripheral cells in the body outside of the cavity will notbe transfected. Thus, there is tissue targeting to the cells within thecavity. For example, gene delivery systems administered into theperitoneal cavity will have access to metastatic tumor cells derivedfrom colon or ovarian cancers that are floating, in the peritoneum orare attached to the surfaces of the peritoneum. Delivery systemsadministered into the plural space should transfect cancer cells in theplural effusion. Delivery systems administered into the cerebral spinalfluid should have access to metastatic cancer cells present there.

With respect to the third point, differentiated cells that are presentin normal tissues are often embedded into an extracellular matrix. Thismatrix can be difficult to penetrate with large particulate deliverysystems. Some cells, such as poorly differentiated tumor cells, that arepresent in cavities can grow outside of the normal extracellular matrixand are therefore more accessible to gene delivery systems. In this waythe delivery system can preferentially transfect those cells that aregrowing outside of the extracellular matrix and not transfect thosecells that are growing within the extracellular matrix. This is anotherform of in vivo, cell type specific targeting. Examples of normal cellsthat are not embedded in an extracellular matrix and are therefore moreaccessible to gene delivery systems are, bronchial airway cells, lungcells in the plural space, and ependimal cells lining the surface of theventricles of the brain. Normal bladder cells that line the surface ofthe bladder are embedded in a tight extracellular matrix and aretherefore not readily accessible to a gene delivery system deliveredinto the bladder, but tumor cells which grow up and out of theextracellular matrix into the bladder vesicle are accessible to genedelivery systems administered into the bladder vesicle. Thus normalbladder tissue would be expected to resist transfection whereas, bladdertumor would be expected to be transfectable.

A preferred application of the intra-cavity delivery embodiment is inthe treatment of peritoneally disseminated cancers. More specifically, amammal bearing peritoneal tumor may be injected i.p. with an effectiveamount of a polynucleotide complexed with a lipid in a physiologicallyacceptable diluent in a total volume sufficient to access the entirebody cavity. The mammal may have tumor ascites in the peritoneal cavityas in an ovarian cancer. In the most preferred application, thismethodology may be used in treating ovarian cancer of a human.

Debulking of tumor ascites is commonly performed on human ovarian cancerpatients. Debulking involves removal of tumor ascites from theperitoneal cavity. In humans bearing ovarian tumor ascites, the ascitesfluid would be debulked by insertion of a catheter i.p. followed byperiodic draining of ascites fluid. It is contemplated that the tumorascites would be debulked before and/or after the i.p. administration ofthe polynucleotide formulation of the present invention.

Transfection efficacy of the intra-cavity delivery embodiment may bedetermined by collecting the tumor ascites and serum at various timesafter the injection and performing diagnostic assays appropriate for theencoded molecule(s). Naturally, other means of determining tumor mass,growth, and viability may also be used to assess the effectiveness ofthe present invention.

Preferred polynucleotides for the intra-cavity delivery embodiment mayencode not only immunogenic molecules such as cytokines (e.g.,interleukins 1-18 and α/β/γ/ω-interferons, colony stimulating factors,e.g., G-CSF, GM-CSF, M-CSF, and tumor necrosis factors), but alsochemokines (e.g., C-X-C and C-C), Class I and II histocompatibilityantigens, costimulatory molecules (e.g., B7-1, B7-2, CAMs, and flt3ligand), growth factors (e.g., epidermal growth factors, fibroblastgrowth factors, transforming growth factors and growth hormone), and thelike. The polynucleotide may also encode bacterial antigens, viralglycoproteins, enzymes (e.g., lysozymes), recombinant antibodies,molecules that interfere with cellular adhesion, adhesion molecules,proliferation and vascular inhibitory factors, ribozymes, and antisenseRNAs targeted toward key oncogenic or tumor growth proteins. Moreover,selective delivery of toxic peptides (e.g., ricin, diphtheria toxin, orcobra venom factor) or proteins capable of synthesizing toxic compounds(e.g. thymidine kinase and cytosine deaminase) to the malignant cellsmay have therapeutic benefits. The polynucleotide may also comprise atumor suppressor gene (e.g., p53). Preferred polynucleotides encodecytokines. Preferred cytokines are IL-2, IFNω, and IFNα. IL-2 is mostpreferred.

For treatment of cancer by any of the above disclosed embodiments, anypolynucleotide encoding an IFNω, or an active fragment thereof, can beused. For example, the polynucleotide construct can be a constructcomprising a polynucleotide that hybridizes under stringent conditionsto the nucleotide sequence of SEQ ID No. 7 or the complement thereof,wherein the polynucleotide sequence encodes a polypeptide that hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro, andone or more cationic compounds selected from the group consisting ofcationic lipids, cationic peptides, cationic proteins, cationicpolymers, and mixtures thereof. Alternatively, the construct can be apolynucleotide construct comprising a polynucleotide that encodes apolypeptide comprising an amino acid sequence which, except for at leastone but not more than 20 amino acid substitutions, deletions, orinsertions, is identical to amino acids −23 to 172 or 1 to 172 in SEQ IDNo. 8, wherein the polypeptide has antiproliferative activity when addedto NIH-OVCAR3 cells in vitro, and one or more cationic compoundsselected from the group consisting of cationic lipids, cationicpeptides, cationic proteins, cationic polymers, and mixtures thereof.Alternatively, the construct can be a polynucleotide constructcomprising a polynucleotide that encodes a polypeptide comprising aminoacids 86-172 in SEQ ID No. 8, wherein the polypeptide hasantiproliferative activity when added to NIH-OVCAR3 cells in vitro; andone or more cationic compounds selected from the group consisting ofcationic lipids, cationic peptides, cationic proteins, cationicpolymers, and mixtures thereof. Preferably, IFNα is encoded bynucleotides 1 to 585 in SEQ ID No. 7 (corresponding to amino acids −23to 172 in SEQ ID No. 8), or by nucleotides 70 to 585 in SEQ ID No. 7(corresponding to amino acids 1 to 172 in SEQ ID No. 8). Morepreferably, the polynucleotide construct is VR4151.

For treatment of cancer, any polynucleotide encoding IFNα, or activefragment thereof, can also be used. For example, the polynucleotideconstruct can be a construct comprising a polynucleotide that hybridizesunder stringent conditions to the nucleotide sequence of SEQ ID No. 9 orthe complement thereof, wherein the polynucleotide sequence encodes apolypeptide that has antiproliferative activity when added to NIH-OVCAR3cells in vitro, and one or more cationic compounds selected from thegroup consisting of cationic lipids, cationic peptides, cationicproteins, cationic polymers, and mixtures thereof. Alternatively, theconstruct can be a polynucleotide construct comprising a polynucleotidethat encodes a polypeptide comprising an amino acid sequence which,except for at least one but not more than 20 amino acid substitutions,deletions, or insertions, is identical to amino acids −23 to 166 or 1 to166 in SEQ ID No. 10, wherein the polypeptide has antiproliferativeactivity when added to NIH-OVCAR3 cells in vitro, and one or morecationic compounds selected from the group consisting of cationiclipids, cationic peptides, cationic proteins, cationic polymers, andmixtures thereof. Alternatively, the construct can be a polynucleotideconstruct comprising a polynucleotide that encodes a polypeptidecomprising amino acids 83-166 in SEQ ID No. 10, wherein the polypeptidehas antiproliferative activity when added to NIH-OVCAR3 cells in vitro;and one or more cationic compounds selected from the group consisting ofcationic lipids, cationic peptides, cationic proteins, cationicpolymers, and mixtures thereof. Preferably, IFNα is encoded bynucleotides 1 to 567 in SEQ ID No. 9 (corresponding to amino acids −23to 166 in SEQ ID No. 10), or by nucleotides 1 to 567 in SEQ ID No. 9(corresponding to amino acids 1 to 166 in SEQ ID No. 10). Preferably,the polynucleotide construct is VR4112.

For polynucleotide constructs that do not contain a polynucleotideencoding IFNω, the polynucleotide construct is preferably a cell-freeconstruct. For polynucleotide constructs that contain a polynucleotideencoding IFNω, the polynucleotide construct can be administered eitherwithin ex vivo cells or free of ex vivo cells or ex vivo cellularmaterial. Preferably, the polynucleotide construct is administered freeof ex vivo cells or ex vivo cellular material.

In the “local delivery” and “intra-cavity delivery” embodiments, thepolynucleotide construct is preferably complexed with one or morecationic compounds. More preferably, the polynucleotide construct iscomplexed with one or more cationic lipids by ionic interaction.Generally, the complex then contacts the cell membrane and istransfected into the cell. This transfection mechanism is referred to as“lipofection,” and is a highly efficient transfection procedure(Felgner, et al., Proc. Natl. Acad. Sci. USA 84:7413-7417, 1987); andFelgner, et al., Nature 337:387-388, 1989). Still more preferably, thepolynucleotide construct is complexed with one or more cationic lipidsand one or more neutral lipids.

For purposes of the present invention, lipid refers to a synthetic ornaturally occurring compound that possesses both a lipophilic region anda polar region, commonly referred to as a head group. Preferred cationiccompounds are cationic lipids. Cationic lipids are described in U.S.Pat. Nos. 4,897,355; 4,946,787; 5,049,386; 5,264,618; 5,279,833;5,334,761; 5,429,127; 5,459,127; 5,589,466; 5,676,954; 5,693,622;5,580,859; 5,703,055; and 5,578,475; and international publications WO04/9469, WO 95/14381, 95/14651, 95/17373, 96/18372, 96/26179, 96/40962,96/40963, 96/41873, and 97/00241, and documents cited therein. Asillustrated in the above-cited patents and patent applications, cationiclipids comprise structural features that may be present in a variety ofcore molecular classes.

Examples of cationic lipids are 5-carboxyspermylglycine dioctadecylamide(DOGS) and dipalmitoyl-phophatidylethanolamine-5-carboxyspermylamide(DPPES). Cationic cholesterol derivatives are also useful, including{3β-[N—N′,N′-dimethylamino)ethane]-carbomoyl}-cholesterol (DC-Chol).Dimethyldioctdecyl-ammonium bromide (DDAB),N-(3-aminopropyl)-N,N-(bis-(2-tetradecyloxyethyl))-N-methyl-ammoniumbromide (PA-DEMO),N-(3-aminopropyl)-N,N-(bis-(2-dodecyloxyethyl))-N-methyl-ammoniumbromide (PA-DELO),N,N,N-tris-(2-dodecyloxy)ethyl-N-(3-amino)propyl-ammonium bromide(PA-TELO), andN′-(3-aminopropyl)((2-dodecyloxy)ethyl)-N²-(2-dodecyloxy)ethyl-1-piperazinaminiumbromide (GA-LOE-BP) can also be employed in the present invention.

Non-diether cationic lipids, such asDL-1,2-dioleoyl-3′-dimethylaminopropyl-p-hydroxyethylammonium (DORIdiester),1-O-oleyl-2-oleoyl-3-dimethylaminopropyl-β-hydroxyethylammonium (DORIester/ether), and their salts promote in vivo gene delivery. Preferredcationic lipids comprise groups attached via a heteroatom attached tothe quaternary ammonium moiety in the head group. A glycyl spacer canconnect the linker to the hydroxyl group.

Preferred cationic lipids are3,5-(N,N-dilysyl)-diaminobenzoyl-3-(DL-1,2-dioleoyl-dimethylaminopropyl-p-hydroxyethylamine)(DLYS-DABA-DORI diester),3,5-(N,N-di-lysyl)diamino-benzoylglycyl-3-(DL-1,2-dioleoyl-dimethylaminopropyl-p-hydroxyethylamine)(DLYS-DABA-GLY-DORI diester), and(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propaniminiumbromide (DMRIE).

Also preferred are(O)-N,N-dimethyl-N-[2-(sperminecarboxamido)ethyl]-2,3-bis(dioleyloxy)-1-propaniminiumpentahydrochloride (DOSPA),(±)-N-(2-aminoethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propaniminiumbromide (β-aminoethyl-DMRIE or PAE-DMRIE) (Wheeler, et al., Biochim.Biophys. Acta 1280:1-11 (1996)), and(±)-N-(3-aminopropyl)-N,N-dimethyl-2,3-bis(dodecyloxy)-1-propaniminiumbromide (GAP-DLRIE) (Wheeler, et al., Proc. Natl. Acad. Sci. USA93:11454-11459 (1996)), which have been developed from DMRIE.

Other examples of DMRIE-derived cationic lipids that are useful for thepresent invention are(±)-N-(3-aminopropyl)-N,N-dimethyl-2,3-(bis-decyloxy)-1-propanaminiumbromide (GAP-DDRIE),(±)-N-(3-aminopropyl)-N,N-dimethyl-2,3-(bis-tetradecyloxy)-1-propanaminiumbromide (GAP-DMRIE),(±)-N-((N″-methyl)-N′-ureyl)propyl-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propanaminiumbromide (GMU-DMRIE),(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(dodecyloxy)-1-propanaminiumbromide (DLRIE), and(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis-([Z]-9-octadecenyloxy)propyl-1-propaniminiumbromide (HP-DORIE).

The lipids of the lipid-containing formulation can comprise a cationiclipid alone, or further comprise a neutral lipid such as cardiolipin,phosphatidylcholine, phosphatidylethanolamine,dioleoylphosphatidylcholine, dioleoylphosphatidyl-ethanolamine,1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE),sphingomyelin, and mono-, di- or tri-acylglycerol. Other additives, suchas cholesterol, fatty acid, ganglioside, glycolipid, neobee, niosome,prostaglandin, sphingolipid, and any other natural or syntheticamphiphiles, can also be used. A preferred molar ratio of cationic lipidto neutral lipid in these lipid-containing formulations is from about9:1 to about 1:9; an equimolar ratio is particularly preferred. Thelipid-containing formulation can further comprise a lyso lipid (e.g.,lysophosphatidylcholine, lysophosphatidyl-ethanolamine, or a lyso formof a cationic lipid).

More preferably, the cationic lipid is(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propaniminiumbromide (DMRIE) and the neutral lipid is1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) such that themass ratio of polynucleotide construct to lipid is from about 10:1 andabout 0.5:1. Still more preferably, the mass ratio of polynucleotideconstruct to lipid is from about 5:1 and about 1:1. Still morepreferably, the mass ratio of polynucleotide construct to lipid is about5:1.

Lipid-containing pharmaceutical composition for use in a complex withthe polynucleotide construct of the present invention can also comprisecationic lipid together with an effective amount of a lysophosphatide.The lysophosphatide can have a neutral or a negative head group.Lysophosphatidylcholine and lysophosphatidyl-ethanolamine are preferred,and 1-oleoyl lysophosphatidylcholine is particularly preferred.Lysophosphatide lipids are advantageously present in thelipid-containing formulation in a 1:2 ratio of lysolipid to cationiclipid. Lyso forms of a cationic lipid can also be used to promotepolynucleotide delivery. These lyso forms are advantageously present ineffective amounts up to about one-third of the total cationic lipid inthe lipid-containing formulations.

In a formulation for preparing DNA:lipid complexes, the cationic lipidcan be present at a concentration of between about 0.1 mole % and about100 mole %, preferably about 5 mole % and 100 mole %, and mostpreferably between about 20 mole % and 100 mole %, relative to otherformulation components present in the formulation. The neutral lipid canbe present in a concentration of between zero and about 99.9 mole %,preferably zero and about 95 mole %, and most preferably zero and about80 mole %. In order to produce lipid vesicles having a net positivecharge, the quantity of the positively charged component must exceedthat of the negatively charged component. The negatively charged lipidcan be present at between zero and about 49 mole %, and preferablybetween zero and about 40 mole %. Cholesterol or a similar sterol can bepresent at between zero to about 80 mole %, and preferably zero andabout 50 mole %.

The polynucleotide to be delivered can be solubilized in a buffer priorto mixing with lipid vesicles. Suitable buffers include, for example,phosphate buffered saline (PBS), normal saline, Tris buffer, and sodiumphosphate vehicle (100-150 mM preferred). Insoluble polynucleotides canbe solubilized in a weak acid or base, and then diluted to the desiredvolume with a neutral buffer such as PBS. The pH of the buffer issuitably adjusted, and moreover, a pharmaceutically acceptable additivecan be used in the buffer to provide an appropriate osmolarity withinthe lipid vesicle.

A lipid solution comprising at least one amphipathic lipid canspontaneously assemble to form primary lipid vesicles, heterogeneous insize. Therefore, according to a preferred method, the lipids of thelipid-containing formulation, comprising at least one cationic lipid,are prepared by dissolution in a solvent such as chloroform and themixture is evaporated to dryness as a film on the inner surface of aglass vessel. On suspension in an aqueous solvent, the amphipathic lipidmolecules assemble themselves into primary lipid vesicles. These primarylipid vesicles may be reduced to a selected mean diameter by means of afreeze-thaw procedure. Vesicles of uniform size can be formed prior todrug delivery according to methods for vesicle production known to thosein the art; for example, the sonication of a lipid solution as describedby Felgner, et al (Proc. Natl. Acad. Sci. USA 84:7413-7417 (1987)) andU.S. Pat. No. 5,264,618.

The term “mammal” is intended to encompass a singular “mammal” andplural “mammals,” and includes, but is not limited to humans; primatemammals such as apes, monkeys, orangutans, and chimpanzees; caninemammals such as dogs and wolves; feline mammals such as cats, lions, andtigers; equine mammals such as horses, donkeys, deer, zebra, andgiraffe; and bears. Preferably, the mammal is a human subject.

Tumor cell formation and growth, also known as “transformation.”describes the formation and proliferation of cells that have lost theirability to control cellular division; that is the cells are cancerous.“Malignant cells” are defined as cells that have lost the ability tocontrol the cell division cycle, leading to a transformed or cancerousphenotype.

The term “non-tumor tissue” is intended to include, but is not limitedto non-tumor bearing tissues such as muscle, skin, brain, lung, liver,spleen, bone marrow, thymus, heart, lymph, blood, bone, cartilage,pancreas, kidney, gall bladder, stomach, intestine, testis, ovary,uterus, rectum, nervous system, eye, gland, or connective tissue.Preferably, the non-tumor tissue is muscle.

Preferably, the polynucleotide construct is delivered to theinterstitial space of a tumor or of non-tumor tissues. “Interstitialspace” comprises the intercellular, fluid, mucopolysaccharide matrixamong the reticular fibers of organ tissues, elastic fibers in the wallsof vessels or chambers, collagen fibers of fibrous tissues, or that samematrix within connective tissue ensheathing muscle cells or in thelacunae of bone. It is similarly the space occupied by the plasma of thecirculation and the lymph fluid of the lymphatic channels.

The pharmaceutical composition and methods of the present invention canbe used to treat a variety of mammalian cancers or tumors. Types ofmammalian cancers and tumors that can be treated using thepharmaceutical composition and methods of the present invention include,but are not limited to all solid tumors, cutaneous tumors, melanoma,malignant melanoma, renal cell carcinoma, colorectal carcinoma, coloncancer, hepatic metastases of advanced colorectal carcinoma, lymphomas(including glandular lymphoma), malignant lymphoma, Kaposi's sarcoma,prostate cancer, kidney cancer, ovarian cancer, lung cancer, head andneck cancer, pancreatic cancer, mesenteric cancer, gastric cancer,rectal cancer, stomach cancer, bladder cancer, leukemia (including hairycell leukemia and chronic myelogenous leukemia), breast cancer,non-melanoma skin cancer (including squamous cell carcinoma and basalcell carcinoma), hemangioma multiple myeloma, and glioma. Preferably,the cancer is melanoma, ovarian cancer, or metastases thereof.

By “treatment” is meant reduction in tumor size, a reduction in the rateof metastasis, and/or a slowing of tumor growth, and/or no worsening indisease over a specified period of time.

A systemic delivery embodiment can be particularly useful for treatingnonlocalized tumors (i.e., leukemia and metastases of a variety oftumors), or a disease category that might be responsive to continuousexposure by the systemic route (i.e., myeloma, chronic myelogenousleukemia, lymphoma). A local delivery embodiment can be particularlyuseful for treating one disease condition that might be responsive tohigh local concentration (i.e., renal cell carcinoma, melanoma). Fortumors involving body cavity of a mammal, “intra-cavity” embodiment ispreferred. In particular, the use of this methodology is envisioned intreating cancers involving (i) the peritoneal cavity—pancreatic cancer,gastric cancer, ovarian cancer, mesenteric cancer, glandular lymphomaand metastatic melanoma; (ii) the thoracic cavity—lung cancer andglandular lymphoma; (iii) the rectal cavity—rectal cancer; (iv) thestomach cavity—stomach cancer; and (v) the urinary bladdervesicle—bladder cancer. When advantageous, systemic, local, and/orintra-cavity delivery can be combined, especially in a mammal having aprimary site of tumor and one or more metastases.

An additional embodiment of the present invention is directed tocombining any of the methods of the present invention with one or moreadditional cancer therapies including, but not limited to bone marrowtransplant, cord blood cell transplant, surgery, chemotherapy, radiationtherapy, and immunotherapy. The polynucleotide construct orpharmaceutical composition of the present invention can be administeredprior to the commencement of one or more of the additional cancertherapies, during the practice of one or more of the additional cancertherapies, and after the end of one or more of the additional cancertherapies.

Types of bone marrow transplant include, but are not limited toautologous bone marrow transplant and heterologous (i.e., from a donor)bone marrow transplant.

Types of surgery include, but are not limited to surgery for breastcancer, prostate cancer, colon cancer, brain cancer, and head and neckcancer.

Chemotherapeutic agents include, but are not limited to alkylatingagents, including mechlorethamine, cyclophosphamide, ifosfamide,melphalan, chlorambucil, dicarbazine, streptazocine, carmustine,lomustine, semustine, chlorozotocin, busulfan, triethylenemelamine,thiotepa, hexamethylmelamine; antimetabolites, including methotrexate;pyrimidine analogs, including fluorouracil, 5-fluorouracil, floxuridine(5′-fluoro-7′-deoxyuridine), idoxuridine, cytarabine,-phosphonoacetyl-L-aspartate, 5-azacytidine, azaribine, 6-azauridine,pyrazofuran, 3-deazauridine, acivicin; purine analogs, includingthioguanine, mercaptopurine, azathioprine, pentostatin,erythrohydroxynonyladenine; vinca alkaloids, including vincristine andvinblastine; epipodophyllotoxins, including etoposide and teniposide;antibiotics, including dactinomycin, daunorubicin, doxorubicin,bleomycin sulfate, plicamycin, mitomycin; enzymes, includingL-asparaginase; platinum coordination complexes, including cisplatin,carboplatin; hydroxyurea, procarbazine, mitotane; and hormones orrelated agents, including adrenocorticosteroids such as prednisone andprednisolone; aminoglutethimide; progestins such as hydroxyprogesteronecaproate, medroxyprogesterone acetate, megesterol acetate, estrogens andandrogens such as diethylstilbestrol, fluoxymesterone, ethynylestradiol, antiestrogens such as tamoxifen, and gonadotropin-releasinghormone analogs such as leuprolide.

The present invention also provides kits for use in treating cancercomprising an administration means and a container means containing oneor more cytokine-expressing polynucleotide constructs in a sterileenvironment. Also provided are kits for use in treating cancercomprising an administration means and a container means containing oneor more cytokine-expressing polynucleotide constructs and one or morecationic compounds in a sterile environment. Examples of cationiccompounds are described above. The cytokine-expressing polynucleotideconstructs and the cationic compounds may be in the same container meansor in separate container means. Preferably, the polynucleotide constructis in the amount of 1 ng to 20 mg.

Container means include glass containers, plastic containers, or stripsof plastic or paper. In one embodiment, the container means is a syringeand the administration means is a plunger. In another embodiment, theadministration means is a catheter.

The cytokine encoded by the polynucleotide construct of the kit of thepresent invention can be an IFNω and one or more additional cytokines,including any of the cytokines described herein. Preferably, thecytokine is IFNω and/or an IFNα. The construct can be in the form of apharmaceutical composition and can contain a pharmaceutically acceptablecarrier. Pharmaceutical compositions are described above. The kit canfurther comprise a pharmaceutically acceptable carrier in a separatecontainer means.

The kit can further comprise an instruction sheet for administration ofthe composition into a mammal. The components of the polynucleotidecomposition are preferably provided as a liquid solution, such as asuspension, a solution, or an emulsion; or in lypholized form as a driedpowder or a cake. If the polynucleotide construct is provided inlypholized form, preferably the kit further comprises a container meanscontaining a suitable vehicle, such as sterile pyrogen-free water, forreconstitution of the lypholized polynucleotide construct, or any bufferdescribed herein, including PBS, normal saline, Tris buffer, and sodiumphosphate vehicle.

The term “cytokine” refers to polypeptides, including but not limited tointerleukins (e.g., IL-1, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8,IL-9, IL-10, IL-11, IL-12, IL-13, IL-14, IL-15, IL-16, IL-17, andIL-18), α interferons (e.g., IFNα), β interferons (e.g., IFNβ), γinterferons (e.g., IFNγ), ω interferon (IFNω), τ interferons (IFNτ),colony stimulating factors (CSFs, e.g., CSF-1. CSF-2, and CSF-3),granulocyte-macrophage colony stimulating factor (GMCSF), epidermalgrowth factor (EGF), fibroblast growth factors (FGFs. e.g., acidicfibroblast growth factor, basic fibroblast growth factor, FGF-1. FGF-2,FGF-3, FGF-4, and FGF-5), transforming growth factor (TGF, e.g., TGFαand TGFβ), platelet-derived growth factor (PDGF), tumor necrosis factors(TNFs, e.g., TNF-α and TNF-β), and insulin-like growth factors (IGFs,e.g., IGF-I and IGF-II).

A “polypeptide” refers to any translation product of a polynucleotide,regardless of the size of the translation product, and regardless ofwhether the translation product is post-translationally modified (e.g.,glycosylated) or not.

The polynucleotide construct of the present invention, whether complexedwith cationic vehicle or not, can be administered by any suitable routeof administration, including intramuscularly, subcutaneously,intravenously, transdermally, intranasally, by inhalation, ortransmucosally (i.e., across a mucous membrane). Similarly, thepharmaceutical composition of the present invention can by administeredby any suitable route, including intramuscularly, into or near a tumor,into a cavity (e.g., intraperitoneally), subcutaneously, intravenously,transdermally, intranasally, by inhalation, or transmucosally (i.e.,across a mucous membrane).

Any mode of administration can be used so long as the mode results inthe expression of one or more cytokines in an amount sufficient todecrease the tumorigenicity of the cancer bearing mammal. This includesneedle injection, catheter infusion, biolistic injectors, particleaccelerators (i.e., “gene guns”), pneumatic “needleless” injectors(e.g., MedEJet, PedoJet, Bioject), gelfoam sponge depots, othercommercially available depot materials, osmotic pumps (e.g., Alzaminipumps), oral or suppositorial solid (tablet or pill) pharmaceuticalformulations, and decanting or topical applications during surgery.Preferred methods include needle injection and catheter infusion.

A “polynucleotide construct” is a polynucleotide molecule that carriesgenetic information for encoding one or more molecules, preferably,cytokines. The polynucleotide material delivered to the cells in vivocan take any number of forms. It can contain the entire sequence or onlya functionally active fragment of a cytokine gene.

The polynucleotide construct comprises at least one polynucleotide(e.g., DNA, RNA, ribozyme, phosphorothioate, or other modified nucleicacid) encoding one or more molecules. Preferred molecules are cytokines.The polynucleotide can be provided in linear, circular (e.g. plasmid),or branched form; and double-stranded or single-stranded form. Thepolynucleotide can involve a conventional phosphodiester bond or anon-conventional bond (e.g., an amide bond as in peptide nucleic acid(PNA)). The choice of polynucleotide encoding a cytokine will depend onthe desired kinetics and duration of expression. When long term deliveryof the polynucleotide construct is desired, the preferred polynucleotideis DNA. Alternatively, when short term delivery is desired, thepreferred polynucleotide is mRNA. RNA will be rapidly translated intopolypeptide, but will be degraded by the target cell more quickly thanDNA. In general, because of the greater resistance of circular DNAmolecules to nucleases, circular DNA molecules will persist longer thanlinear polynucleotides, and they will be less likely to causeinsertional mutation by integrating into the target genome.

In one embodiment, the polynucleotide sequence encoding one or morecytokines is RNA. Most preferably, the RNA is messenger RNA (mRNA).Methods for introducing RNA sequences into mammalian cells is describedin U.S. Pat. No. 5,580,859. A viral alphavector, a non-infectious vectoruseful for administering RNA, may be used to introduce RNA intomammalian cells. Methods for the in vivo introduction of alphaviralvectors to mammalian tissues are described in Altman-Hamamdzic, S., etal., Gene Therapy 4: 815-822 (1997). Preferably, the polynucleotidesequence encoding one or more cytokines is DNA. In a DNA construct, apromoter is preferably operably linked to the polynucleotide encoding acytokine. The promoter may be a cell-specific promoter that directssubstantial transcription of the DNA only in predetermined cells. Othertranscription control elements, besides a promoter, can be included inthe polynucleotide construct to direct cell-specific transcription ofthe DNA.

An operable linkage is a linkage in which a polynucleotide sequenceencoding a cytokine is connected to one or more regulatory sequence insuch a way as to place expression of the cytokine sequence under theinfluence or control of the regulatory sequence(s). Two DNA sequences(such as a coding sequence and a promoter region sequence linked to the5′ end of the coding sequence) are operably linked if induction ofpromoter function results in the transcription of mRNA encoding thedesired polypeptide and if the nature of the linkage between the two DNAsequences does not (1) result in the introduction of a frame-shiftmutation, (2) interfere with the ability of the expression regulatorysequences to direct the expression of the polypeptide, antisense RNA, or(3) interfere with the ability of the DNA template to be transcribed.Thus, a promoter region would be operably linked to a DNA sequence ifthe promoter was capable of affecting transcription of that DNAsequence.

Preferably, the polynucleotide construct is a circular or linearizedplasmid containing non-infectious nucleotide sequence. A linearizedplasmid is a plasmid that was previously circular but has beenlinearized, for example, by digestion with a restriction endonuclease.The polynucleotide sequence encoding a cytokine may comprise a sequencewhich directs the secretion of the polypeptide.

“Non-infectious” means that the polynucleotide construct does not infectmammalian cells. Thus, the polynucleotide construct can containfunctional sequences from non-mammalian (e.g., viral or bacterial)species, but the construct does not contain non-mammalian nucleotidesequences that facilitate infection of the construct into mammaliancells.

Non-integrating means that the polynucleotide construct does notintegrate into the genome of mammalian cells. The construct can be anon-replicating DNA sequence, or specific replicating sequencesgenetically engineered to lack the ability to integrate into the genome.The polynucleotide construct does not contain functional sequences thatfacilitate integration of the cytokine-encoding polynucleotide sequenceinto the genome of mammalian cells.

The polynucleotide construct is assembled out of components wheredifferent selectable genes, origins, promoters, introns, 5′ untranslated(UT) sequence, terminators, polyadenylation signals, 3′ UT sequence, andleader peptides, etc. are put together to make the desired vector. Theprecise nature of the regulatory regions needed for gene expression canvary between species or cell types, but shall in general include, asnecessary, 5′ non-transcribing and 5′ non-translating (non-coding)sequences involved with initiation of transcription and translationrespectively, such as the TATA box, capping sequence, CAAT sequence, andthe like, with those elements necessary for the promoter sequence beingprovided by the promoters of the invention. Such transcriptional controlsequences can also include enhancer sequences or upstream activatorsequences, as desired.

The polynucleotide construct can be an expression vector. A typicalmammalian expression vector contains the promoter element, whichmediates the initiation of transcription of mRNA, the polypeptide codingsequence, and signals required for the termination of transcription andpolyadenylation of the transcript. Additional elements includeenhancers, Kozak sequences and intervening sequences flanked by donorand acceptor sites for RNA splicing. Highly efficient transcription canbe achieved with the early and late promoters from SV40, the longterminal repeats (LTRS) from retroviruses, e.g., RSV, HTLVI, HIVI, MPSVand the immediate early promoter of the cytomegalovirus (CMV IEP).However, cellular elements can also be used (e.g., the human actinpromoter, metallothionein promoter). In humans, CMV IEP is preferred.Suitable expression vectors for use in practicing the present inventioninclude, for example, vectors such as PSVL and PMSG (Pharmacia, Uppsala,Sweden), pRSVcat (ATCC 37152), pSV2dhfr (ATCC 37146) and pBC12MI (ATCC67109), VR1012, VR1055, and pcDNA3 (Invitrogen, San Diego, Calif.). Allforms of DNA, whether replicating or non-replicating, which do notbecome integrated into the genome, and which are expressible, are withinthe methods contemplated by the invention.

The vector containing the DNA sequence (or the corresponding RNAsequence) which can be used in accordance with the invention can be aeukaryotic expression vector. Techniques for obtaining expression ofexogenous DNA or RNA sequences in a host are known. See, for example,Korman, et al., Proc. Nat. Acad. Sci. (USA) 84:2150-2154 (1987).

Secretion of a cytokine from a cell can be facilitated by a leader orsecretory signal sequence. In a preferred embodiment, either the nativeleader sequence of a cytokine is used, or a functional derivative ofthat sequence that retains the ability to direct the secretion of thepeptide that is operably linked to it. Alternatively, a heterologousmammalian leader sequence, or a functional derivative thereof, may beused. For example, the wild-type leader sequence may be substituted withthe leader sequence of human tissue plasminogen activator or mouseβ-glucuronidase.

For the methods of the present invention, a single polynucleotideconstruct containing more than one polynucleotide sequences encoding oneor more molecules, or more than one polynucleotide constructs eachcontaining polynucleotide sequences encoding one or more molecules maybe co-injected or sequentially injected. For example, a singlepolynucleotide construct containing one polynucleotide encoding aninterferon and another polynucleotide encoding an additional cytokine oran immunomodulatory molecule, i.e., MHC class I antigen, tumor antigen,and co-stimulatory molecule, can be injected. Alternatively, twopolynucleotide construct can be injected where one encodes a cytokine toenhance anti-tumor efficacy of the other gene product. For example, anIFNω, IFNα, IL-12 or IL-2-expressing polynucleotide construct can beco-injected with a polynucleotide construct encoding a differentcytokine. More specifically, an IL-2 expressing plasmid could beco-injected with a G-CSF or GM-CSF expressing plasmid. Alternatively,one or more plasmids could be administered initially and otherplasmid(s) could be administered subsequently at various time intervals.Combination of the present invention with therapeutic agents such aslymphokine-activated killer cells (LAK) and tumor-infiltratinglymphocytes (TIL) is also envisioned.

It will be recognized in the art that some amino acid sequences of thepolypeptides described herein can be varied without significant effecton the functional activity of the polypeptides. If such differences insequence are contemplated, it should be remembered that there will becritical areas on the polypeptide which determine activity. Suchvariations include deletions, insertions, inversions, repeats, and typesubstitutions. Guidance concerning which amino acid changes are likelyto be phenotypically silent can be found in Bowie, J. U., et al,“Deciphering the Message in Protein Sequences: Tolerance to Amino AcidSubstitutions,” (Science 247:1306-1310 (1990)). Compositions within thescope of the invention can be assayed according to the antiproliferationassay described herein. Amino acids that are critical for cytokineactivity can also be determined by structural analysis such ascrystallization, nuclear magnetic resonance or photoaffinity labeling(Smith, et al., J. Mol. Biol. 224:899-904 (1992) and de Vos, et al.Science 255:306-312 (1992)).

The present invention further relates to using variants of thecytokine-encoding polynucleotide, which encode portions, analogs orderivatives of the cytokine. Variants may occur naturally, such as anatural allelic variant. By an “allelic variant” is intended one ofseveral alternate forms of a gene occupying a given locus on achromosome of an organism. Genes II, Lewin, B., ed., John Wiley & Sons,New York (1985). Non-naturally occurring variants may be produced usingart-known mutagenesis techniques.

Alterations in the coding regions may produce conservative ornon-conservative amino acid substitutions, deletions or additions.Especially preferred among these are silent substitutions, additions anddeletions, which do not alter the properties and activities of thecytokine or portions thereof. Also especially preferred in this regardare conservative substitutions. For example, aromatic amino acids thatcan be conservatively substituted for one another include phenylalanine,tryptophan, and tyrosine. Hydrophobic amino acids that can beconservatively substituted for one another include leucine, isoleucine,and valine. Polar amino acids that can be conservatively substituted forone another include glutamine and asparagine. Basic amino acids that canbe conservatively substituted for one another include arginine, lysine,and histidine. Acidic amino acids that can be conservatively substitutedfor one another include aspartic acid and glutamic acid. Small aminoacids that can be conservatively substituted for one another includealanine, serine, threonine, methionine, and glycine.

Substitutions, deletions, or insertions can be made outside of theregion encoding the shortest active fragment of the cytokine, withoutaffecting the activity of the cytokine. Further, mutated proteins (ormuteins) often retain a biological activity that is similar to that ofthe naturally occurring protein. For example, Gayle and coworkers (J.Biol. Chem. 268: 22105-22111 (1993)) conducted an extensive mutationalanalysis of the human cytokine IL-1α. They used random mutagenesis togenerate over 3,500 individual IL-1α mutants with an average of 2.5amino acid changes per mutein over the entire length of the molecule.Multiple mutations were examined at every possible amino acid and, onaverage, each mutein's amino acid sequence was 98.4% identical to thatof naturally occurring IL-1α. The investigators observed that most ofthe molecule could be mutated with little effect on either binding orbiological activity, and that 75% of the molecule may not contributesignificantly to the biological activity of the molecule.

Similarly, Gronenborn and colleagues (FEBS Letters 231:135-138 (1988))analyzed the receptor binding activity of six mutant IL-1α polypeptides.Each mutant contained a single amino acid alteration from the naturallyoccurring IL-1α polypeptide and was examined under four sets ofexperimental conditions. In this study, the investigators found verylittle difference between the receptor binding activity of the mutantsand naturally occurring IL-1α.

Further, Zurawski and colleagues (EMBO J. 12: 5113-5119 (1993)) studiedresidues 41-142 of mIL-2 by generating 1,090 muteins. The extent of themutagenesis was such that there was an average of 111 different aminoacid substitutions per naturally occurring amino acid residue, with theexception of the extreme N- and C-termini and residues 31-40. The mIL-2muteins were assayed for specific activity and compared to that ofnaturally occurring mIL-2. The degree to which the specific activity wasantagonized by a previously characterized mIL-2 mutant was alsoassessed. The investigators observed that in the 149 residue mIL-2protein, only 23 residues are important for interaction with IL-2R, 18residues are presumed to be part of the structural core, and threeadditional residues are important for structure. 98 mIL-2 residues (or65% of the protein) were assigned as relatively unimportant residues.

The polynucleotide and amino acid sequences encoding an IFNω include thesequences for the complete IFNω and the mature IFNω set forth in U.S.Pat. No. 4,917,887; European Patent Publication No. 0 170 204 BI; andCapon, D. J., et al., Molec. Cell. Biol. 5: 768-779 (1985); Hauptmann,R. and P. Swetly, Nucl. Acids Res. 13: 4739-4749 (1985); Adolf, G. R.,et al., Biochim. Biophys. Acta 1089: 167-174 (1991); Mege, D., et al, J.Interf. Res. 11: 341-350 (1991); Charlier, M., et al., J. Interf. Res.13 313-322 (1993); Hughes, A. L., J. Mol. Evol. 41: 539-548 (1995); andRoberts, R. M., et al., Prog. Nucl. Acid Res. Molec. Biol. 56:287-325,edited by W. E. Cohn, Academic Press (1997).

The polynucleotide and amino acid sequences encoding IFNα include thesequences for the complete IFNα and the mature IFNα set forth in U.S.Pat. Nos. 4,530,901; 4,695,543; 4,695,623; 4,748,233; 4,892,743;4,897,471; 4,973,479; 4,975,276; and 5,098,703; and in Pestka, S.,Methods Enzymol. 119: 3-14 (1986); Hughes, A. L., J. Mol. Evol. 41:539-548 (1995); and Roberts, R. M., et al., Prog. Nucl. Acid Res. Molec.Biol. 56:287-325, edited by W. E. Cohn, Academic Press (1997).

The polynucleotide and amino acid sequences encoding an IL-2 include thesequences for the complete human IL-2 and mature IL-2 set forth inLupker, J. et al., EP 0307285-A3 (1989), U.S. Pat. No. 5,641,665, Maedaet al., Biochem. Biophys. Res. Commun. 115:1040-1047 (1983), Mita etal., Biochem. Biophys. Res. Commun. 117:114-121 (1983), Taniguchi etal., Nature 302:305-310 (1983), Devos et al., Nucleic Acid Res.11:4307-4323 (1983), Fujita et al. Proc. Natl. Acad. Sci. USA80:74347-7441 (1983), Clark et al., Proc. Natl. Acad. Sci. USA81:2543-2547 (1984) and Cullen, DNA 7:645-650 (1988).

The polynucleotide sequences encoding an IFNω, an IFNα, and an IL-2 alsoinclude sequences that encode the complete polypeptide encoded by thenucleotide sequences set forth in SEQ ID Nos. 7, 9 and 13, respectively,and the mature polypeptides encoded by nucleotide sequences set forth inSEQ ID Nos. 7, 9 and 13, respectively. The polynucleotide sequencesencoding IL-2 further includes the sequence that encodes the completeIL-2 polypeptide encoded by the nucleotide sequence set forth in SEQ IDNo. 25, shown as SEQ ID No. 26.

Thus, a polynucleotide sequence encoding a polypeptide of the presentinvention can encode a polypeptide having one to twenty amino acidsubstitutions, deletions or insertions, either from natural mutations orhuman manipulation, relative to the full length or mature IFNα, IFNω, orIL-2. Preferably, no more than one to fifteen substitutions, deletionsor insertions are present, relative to the full length or mature IFNα,IFNω, or IL-2 (excluding the signal sequence). More preferably, no morethan one to ten substitutions, deletions or insertions are present.Still more preferably, no more than one to five substitutions, deletionsor insertions are present.

Determining an effective amount of substance to be delivered can dependupon a number of factors including, for example, the chemical structureand biological activity of the substance, the age and weight of themammal, the precise condition requiring treatment and its severity, andthe route of administration. The precise amount, number of doses, andtiming of doses will be determined by the attending physician orveterinarian.

If the polynucleotide construct of the present invention is administeredas a pharmaceutical composition, the pharmaceutical composition can beformulated according to known methods for preparing pharmaceuticalcompositions, whereby the substance to be delivered is combined with apharmaceutically acceptable carrier vehicle. Suitable vehicles and theirpreparation are described, for example, in Remington's PharmaceuticalSciences, 16^(th) Edition, A. Osol, Ed., Mack Publishing Co., Easton,Pa. (1980), and Remington's Pharmaceutical Sciences, 19^(th) Edition, A.R. Gennaro, Ed., Mack Publishing Co., Easton, Pa. (1995).

The pharmaceutical composition can be in the form of an emulsion, gel,solution, suspension, or other form known in the art. Optionally, it cancontain one or more lipids as described above. In addition, thepharmaceutical composition can also contain pharmaceutically acceptableadditives including, for example, diluents, binders, stabilizers, andpreservatives. Administration of pharmaceutically acceptable salts ofthe polynucleotides described herein is preferred. Such salts can beprepared from pharmaceutically acceptable non-toxic bases includingorganic bases and inorganic bases. Salts derived from inorganic basesinclude sodium, potassium, lithium, ammonium, calcium, magnesium, andthe like. Salts derived from pharmaceutically acceptable organicnon-toxic bases include salts of primary, secondary, and tertiaryamines, basic amino acids, and the like.

For aqueous pharmaceutical compositions used in vivo, sterilepyrogen-free water is preferred. Such formulations will contain aneffective amount of the substance together with a suitable amount ofvehicle in order to prepare pharmaceutically acceptable compositionssuitable for administration to a human or animal.

A pharmaceutical composition can be in solution form, or alternatively,in lyophilized form for reconstitution with a suitable vehicle, such assterile, pyrogen-free water. Both liquid and lyophilized forms willcomprise one or more agents, preferably buffers, in amounts necessary tosuitably adjust the pH of the injected solution.

The container in which the pharmaceutical formulation is packaged priorto use can comprise a hermetically sealed container enclosing an amountof the lyophilized formulation or a solution containing the formulationsuitable for a pharmaceutically effective dose thereof, or multiples ofan effective dose. The pharmaceutical formulation is packaged in asterile container, and the hermetically sealed container is designed topreserve sterility of the pharmaceutical formulation until use.Optionally, the container can be associated with administration meansand or instruction for use.

It will be apparent to one skilled in the art, in view of the followingdetailed description and the claims appended hereto, that varioussubstitutions and modifications may be made to the present inventionwithout departing from the scope of the invention as claimed.

The present invention is broadly directed to compositions and methodsfor improving the effectiveness of polypeptide delivery into avertebrate by administering a polynucleotide encoding the polypeptide tothe vertebrate's cells in vivo. Such compositions comprise apolypeptide-encoding polynucleotide and sodium phosphate dissolved in anaqueous solution. In one preferred embodiment, about 1 ng to about 30 mgof a polynucleotide is dissolved in a solution of about 20 mM to about300 mM sodium phosphate. In another preferred embodiment, about 1 ng toabout 30 mg of a polynucleotide is associated with a cationic lipid inan aqueous solution of about 0.1 to about 150 mM sodium phosphate. Inthis embodiment, the aqueous solution is substantially free of chlorideanion.

In this manner, the present invention provides a method of enhancing thelevel of polypeptide expression from delivered polynucleotides in vivoand/or facilitating uptake of the polynucleotides by vertebrate cells.Delivery methods utilizing the compositions of the present inventionsignificantly enhance the levels of in vivo transfection and in vivopolypeptide expression compared with traditional methods, i.e., deliveryof a polypeptide-encoding polynucleotide in a solution of normal saline(about 154 mM NaCl) or phosphate buffered saline (“PBS”: about 154 mMNaCl, about 10 mM sodium phosphate at pH 7).

It is to be noted that the term “a” or “an” entity, refers to one ormore of that entity; for example, “a polynucleotide,” is understood torepresent one or more polynucleotides. As such, the terms “a” (or “an”),“one or more,” and “at least one” can be used interchangeably herein.

The term “vertebrate” is intended to encompass a singular “vertebrate”as well as plural “vertebrates,” and comprises mammals and birds, aswell as fish, reptiles, and amphibians.

The terms “saline” or “normal saline” as used herein refer to an aqueoussolution of about 145 mM to about 155 mM sodium chloride, preferablyabout 154 mM sodium chloride. The terms “phosphate buffered saline” or“PBS” refer to an aqueous solution of about 145 mM to about 155 mMsodium chloride, preferably about 154 mM sodium chloride, and about 10mM sodium phosphate, at a pH ranging from about 6.0 to 8.0, preferablyat a pH ranging from about 6.5 to about 7.5, most preferably at pH 7.0.

As used herein, an “ion,” an “ionic molecule,” or an “ionic compoundrefers to a charged molecule or compound. A “cation,” a “cationicmolecule, or a “cationic compound” refers to a positively chargedmolecule or compound, for example Na⁺. An “anion,” an “anionicmolecule,” or an “anionic compound” refers to a negatively chargedmolecule or compound, for example, HPO₄ ²⁻ or H₂PO₄ ⁻. Cations andanions may have any number of positive or negative charges,respectively, i.e., they may be monovalent like Na⁺ or multivalent,e.g., divalent such as Ca²⁺, or trivalent such as Al³⁺. Anions can beeither inorganic or organic, examples of the latter being pyruvate orcitrate anions.

Salts and Associated Formulations

Certain embodiments of the present invention comprise the salt sodiumphosphate. As used herein, a “salt” of the present invention is acompound having a positively charged cation, C, and a negatively chargedanion, A. A salt may be in a solid crystalline form, but preferably forthe present invention, is dissolved in an aqueous solution, i.e., liquidwater. As used herein, “sodium phosphate” can be either the monobasicform, e.g., Na₂HPO₄, or the dibasic form, e.g., NaH₂PO₄, but a mixtureof the two, resulting in a desired pH, is most preferred. Accordingly,as used herein the term “sodium phosphate” refers to a mixture of thedibasic and monobasic forms of the salt to reach a given pH.

The pH values for the sodium phosphate solution of the present inventioncan range from about pH 4 to about pH 10, depending on the properties ofthe particular salt solution. These pH values include about pH 4, aboutpH 4.5, about pH 5, about pH 5.5., about pH 6, about pH 6.5, about pH 7,about pH 7.5. about pH 8, about pH 8.5, about pH 9, about pH 9.5, andabout pH 10. As used herein, the term “about” when referring to pHvalues indicates that the pH value may vary by as much as 0.4 pH unitsin either direction due to, for example, standard error or equipmenterror. Preferred pH values for a solution of sodium phosphate are fromabout pH 6 to about pH 8. More preferred pH values for a solution ofsodium phosphate range from about pH 6.5 to about pH 7.5. Even morepreferred pH values for a solution of sodium phosphate or potassiumphosphate range from about 6.8 to about 7.4.

Sodium phosphate is preferably dissolved in aqueous solution at aconcentration which enhances entry of a polypeptide-encodingpolynucleotide into vertebrate cells in vivo, and/or enhancespolypeptide expression, relative to saline, PBS, or water.

Certain embodiments of the present invention are drawn to compositionscomprising about 1 ng to about 30 mg of a polynucleotide in aqueoussolution, where the polynucleotide operably encodes a polypeptide withinvertebrate cells in vivo; and sodium phosphate dissolved in the aqueoussolution at a molar concentration from about 20 mM to about 300 mM, andreaction, association, or dissociation products thereof. The presentinvention is further drawn to methods to use such a composition, methodsto make such a composition, and pharmaceutical kits.

The term “sodium phosphate dissolved in aqueous solution at a givenmolar concentration” means that the molecular mass, e.g., in grams, of acrystallized form of sodium phosphate required to produce a given volumeof a solution of a given molar concentration is calculated based on themolecular weight of the particular crystalline form. That amount ofcrystals is weighed out using standard laboratory procedures, thecrystals are added to a volume of water or other aqeuous solution whichis slightly less than the final desired volume, the liquid is mixeduntil the crystals are fully dissolved, and then the volume of theliquid is brought up to the final desired volume.

The term “reaction, association, or dissociation products thereof”refers to any ionic interactions which may be formed in the aqueoussolution once the salt crystals are dissolved. For example, once sodiumphosphate is dissolved in an aqueous solution, the cations and anionsdisassociate and are free in solution to interact with other cations oranions that may be present in the solution, including, for example, anegatively-charged polynucleotide molecule. The interactions takingplace in a complex aqueous sodium phosphate solution, except for theprecipitation of insoluble salt complexes, are transient and reversible,and cannot be precisely predicted at any point in time. Therefore, oncean aqueous solution comprising sodium phosphate at a certain molarconcentration is prepared, the interactions in the solution may includereaction products other than the interaction of the cation and anionwhich composed the sodium phosphate crystals that were added to thesolution as described above.

Preferably in the present embodiment, sodium phosphate is dissolved inaqueous solution at a molar concentration ranging from about 25 mM toabout 290 mM, from about 30 mM to about 280 mM, from about 35 mM toabout 270 mM, from about 40 mM to about 260 mM, from about 45 mM toabout 255 mM, from about 50 mM to about 250 mM, from about 55 mM toabout 245 mM, from about 60 mM to about 240 mM, from about 65 mM toabout 235 mM, from about 70 mM to about 230 mM, from about 75 mM toabout 225 mM, from about 80 mM to about 220 mM, from about 85 mM toabout 215 mM, from about 90 mM to about 210 mM, from about 95 mM toabout 205 mM, from about 100 mM to about 200 mM, from about 105 mM toabout 195 mM, from about 110 mM to about 190 mM, from about 115 mM toabout 185 mM, from about 120 mM to about 180 mM, from about 125 mM toabout 175 mM, from about 130 mM to about 170 mM, from about 135 mM toabout 165 mM, from about 140 mM to about 160 mM, and from about 145 mMto about 155 mM.

More preferably in the present embodiment, sodium phosphate is dissolvedin aqueous solution at a molar concentration of about 20 mM, about 25mM, about 30 mM, about 35 mM, about 40 mM, about 45 mM, about 50 mM,about 55 mM, about 60 mM, about 65 mM, about 70 mM, about 75 mM, about80 mM, about 85 mM, about 90 mM, about 95 mM, about 100 mM, about 105mM, about 110 mM, about 115 mM, about 120 mM, about 125 mM, about 130mM, about 135 mM, about 140 mM, about 145 mM, about 150 mM, about 155mM, about 160 mM, about 165 mM, about 170 mM, about 175 mM, about 180mM, about 185 mM, about 190 mM, about 200 mM, about 205 mM, about 210mM, about 215 mM, about 220 mM, about 225 mM, about 230 mM, about 235mM, about 240 mM, about 245 mM, about 250 mM, about 255 mM, about 260mM, about 265 mM, about 270 mM, about 275 mM, about 280 mM, about 285mM, about 290 mM, about 295 mM, and about 300 mM.

Even more preferably in the present embodiment, sodium phosphate isdissolved in aqueous solution at a molar concentration of about 100 toabout 200 mM. Most preferably, sodium phosphate is dissolved in aqueoussolution at a molar concentration of about 150 mM.

As used herein, a phrase such as “a molar concentration of about 150 mM”refers to the range of molar concentrations approaching 150 mM to thebest approximation obtainable by one of ordinary skill in the art usingstandard laboratory equipment and methods. For example, “the salt sodiumphosphate dissolved in aqueous solution of about 150 mM,” prepared usingordinary laboratory balances and measuring glassware, and usinggenerally accepted techniques, may range anywhere from approximately 145mM to approximately 155 mM based on the standard error inherent inpreparing chemical solutions. Such a standard error range would be wellunderstood by one of ordinary skill in the art to be equivalent to“about 150 mM.”

According to the present embodiment, compositions comprising about 1 ngto about 30 mg of a polynucleotide in aqueous solution and sodiumphosphate dissolved in the aqueous solution at a molar concentrationfrom about 20 mM to about 300 mM as described above may further comprisechloride ion, represented by the symbol Cl⁻, in the aqueous solution ata molar equivalent concentration of 0 (zero) mM to about 125 mM. By“molar equivalent” is meant the molar concentration of chloride ion insolution, as opposed to the molar concentration of the salt added to theaqueous solution. For example, chloride ion may be added to the aqueoussolution as part of certain salt crystals dissolved in the solution,such as sodium chloride (NaCl) or calcium chloride (CaCl₂). Each mole ofsodium chloride crystals added to an aqueous solution will add one moleequivalent of chloride ion to the solution, where each mole of calciumchloride crystals added to an aqueous solution will add two moleequivalents of chloride ion to the solution. Alternatively, chloride ionmay be added to the aqueous solution as part of an acid or base such ashydrogen chloride or ammonium chloride.

Preferably, chloride ion is present in the aqueous solution at a molarequivalent concentration ranging from 0 mM to about 120 mM, from 0 mM toabout 115 mM, from 0 mM to about 110 mM, from 0 mM to about 105 mM, from0 mM to about 100 mM, from 0 mM to about 95 mM, from 0 mM to about 90mM, from 0 mM to about 85 mM, from 0 mM to about 80 mM, from 0 mM toabout 75 mM, from 0 mM to about 70 mM, from 0 mM to about 65 mM, from 0mM to about 60 mM, from 0 mM to about 55 mM, from 0 mM to about 50 mM,from 0 mM to about 45 mM, from 0 mM to about 40 mM, from 0 mM to about35 mM, from 0 mM to about 30 mM, from 0 mM to about 25 mM, from 0 mM toabout 20 mM, from 0 mM to about 15 mM, from 0 mM to about 10 mM, or from0 mM to about 5 mM.

More preferably, chloride ion is present in the aqueous solution at amolar concentration of about 120 mM, about 115 mM, about 110 mM, about105 mM, about 100 mM, about 95 mM, about 90 mM, about 85 mM, about 80mM, about 75 mM, about 70 mM, about 65 mM, about 60 mM, about 55 mM,about 50 mM, about 45 mM, about 40 mM, about 35 mM, about 30 mM, about25 mM, about 20 mM, about 15 mM, about 10 mM, about 5 mM, or 0 mM.

Most preferably, the aqueous solution is substantially free of chlorideion. As used herein, the phrase “substantially free of chloride ion”indicates that the amount of chloride ion added into the composition isinsubstantial and that the addition cannot alter the transcription-and/or expression-enhancing activity of the composition at a significantlevel. The phrase “essentially free of chloride ion” indicates that nochloride ion is intentionally added to the composition. However, somechloride ion may be present due to, for example, impurities in othercomponents of the composition.

In certain embodiments, described in more detail below, compositions ofthe present invention may further comprise one or more transfectionfacilitating materials including, but not limited to, materials such ascationic lipids, calcium phosphate, alum, gold, tungsten, or other metalparticles, peptides, proteins, and polymers. However, compositions ofthe present embodiment, which comprise a polynucleotide in aqueoussolution and sodium phosphate dissolved in the aqueous solution at amolar concentration from about 20 mM to about 300 mM as described above,are preferably free of cationic lipids.

Accordingly a preferred embodiment of the present invention is acomposition comprising: about 1 ng to about 30 mg of a polynucleotide inaqueous solution, where the polynucleotide operably encodes apolypeptide within vertebrate cells in vivo; sodium phosphate dissolvedin the aqueous solution at a molar concentration from about 20 mM toabout 300 mM, and reaction, association, or dissociation productsthereof, where the composition is free of cationic lipids.

Further embodiments of the present invention are drawn to compositionscomprising: about 1 ng to about 30 mg of a polynucleotide in aqueoussolution, where the polynucleotide operably encodes a polypeptide withinvertebrate cells in vivo; sodium phosphate dissolved in the aqueoussolution at a molar concentration from about 0.1 mM to about 150 mM, andreaction, association, or dissociation products thereof; a cationiclipid suspended in said aqueous solution; and where the aqueous solutionis substantially free of chloride anion. The present invention isfurther drawn to methods to use such a composition, methods to make sucha composition, and pharmaceutical kits.

Preferably, sodium phosphate is dissolved in aqueous solution at a molarconcentration ranging from about 0.1 mM to about 145 mM, from about 0.1mM to about 140 mM, from about 0.1 mM to about 135 mM, from about 0.1 mMto about 130 mM, from about 0.1 mM to about 125 mM, from about 1 mM toabout 120 mM, from about 1 mM to about 115 mM, from about 1 mM to about0 mM, from about 1 mM to about 105 mM, from about 1 mM to about 100 mM,from about 1 mM to about 95 mM, from about 1 mM to about 90 mM, fromabout 1 mM to about 85 mM, from about 1 mM to about 80 mM, from about 1mM to about 75 mM, from about 1 mM to about 70 mM, from about 1 mM toabout 65 mM, from about 1 mM to about 60 mM, from about 1 mM to about 55mM, from about 1 mM to about 50 mM, from about 1 mM to about 45 mM, fromabout 1 mM to about 40 mM, from about 1 mM to about 35 mM, from about 1mM to about 30 mM, from about 1 mM to about 25 mM, from about 1 mM toabout 20 mM, from about 1 mM to about 15 mM, from about 1 mM to about 10mM, from about 1 mM to about 5 mM, from about 1 mM to about 4.0 mM, fromabout 1 mM to about 3.0 mM, or from about 1 mM to about 2.5 mM.

More preferably, sodium phosphate is dissolved in aqueous solution at amolar concentration of about 145 mM, about 140 mM, about 135 mM, about130 mM, about 125 mM, about 120 mM, about 115 mM, about 110 mM, about105 mM, about 100 mM, about 95 mM, about 90 mM, about 85 mM, about 80mM, about 75 mM, about 70 mM, about 65 mM, about 60 mM, about 55 mM,about 50 mM, about 45 mM, about 40 mM, about 35 mM, about 30 mM, about25 mM, about 20 mM, about 15 mM, about 10 mM, about 5 mM, about 4.0 mM,about 3.0 mM, about 2.5 mM, about 2.0 mM, about 1.5 mM, about 1.0 mM,about 0.5 mM, or about 0.1 mM.

Even more preferably, sodium phosphate is dissolved in aqueous solutionat a molar concentration of about 1 mM to 10 mM, with about 2.5 mM beingmost preferred.

Those embodiments of the present invention comprising sodium phosphatedissolved in the aqueous solution at a molar concentration from about0.1 mM to about 150 mM, and which are substantially free of chloride ionalso comprise a cationic lipid suspended in the aqueous solution.Cationic lipids are described in more detail above. While not beingbound by theory, cationic lipids are thought to interact with anionicpolynucleotide molecules in solution, and the complexes formed therebyare thought to have an improved ability to enter into vertebrate cells.

That sodium phosphate and sodium phosphate solutions disclosed hereinwere effective in increasing expression of polypeptides encoded bypolynucleotides delivered to vertebrate cells in vivo relative to salineor PBS was unexpected in view of results showing that other saltsolutions have no enhancing effect on expression of polypeptides encodedby polynucleotides delivered to vertebrate cells in vivo, or even hindersuch expression. For example, the following salt solutions had noability to enhance, relative to a salt solution consisting essentiallyof normal saline, the entry of polynucleotides into vertebrate cells invivo, and/or the in vivo expression of polypeptides encoded by suchpolynucleotides: 150 mM potassium chloride, 150 mM magnesium chloride,150 mM calcium chloride, 150 mM zinc chloride, 150 mM ferrous chloride,150 mM magnesium phosphate, 150 mM calcium phosphate, 150 mM aluminumphosphate, 150 mM ferric phosphate, 150 mM sodium citrate, and 150 mMsodium oxalate. See Table 10.

Polynucleotides

The present invention covers the delivery to a vertebrate of apolypeptide-encoding polynucleotide in a detectable amount. Preferably,the encoded polypeptide is expressed in vivo in the vertebrate in anamount sufficient to provide an immunogenic, immunomodulatory,therapeutic, or corrective effect to a vertebrate in need of suchtreatment.

The term “nucleic acid” is intended to encompass a singular “nucleicacid” as well as plural “nucleic acids,” and refers to an isolatedmolecule or construct, e.g., virus genomes (preferably non-infectious),messenger RNA (mRNA), plasmid DNA (pDNA), or derivatives of pDNA (e.g.,minicircles as described in (Darquet, A-M et al., Gene Therapy4:1341-1349 (1997)) comprising a polynucleotide. A nucleic acid may beprovided in linear (e.g., mRNA), circular (e.g., plasmid), or branchedform as well as double-stranded or single-stranded forms. A nucleic acidmay comprise a conventional phosphodiester bond or a non-conventionalbond (e.g., an amide bond, such as found in peptide nucleic acids(PNA)).

The term “polynucleotide” refers to any one or more nucleic acidsegments, e.g., DNA or RNA fragments, present in a nucleic acid orconstruct. Two or more polynucleotides of the present invention can bepresent in a single nucleic acid construct, e.g., on a single plasmid,or in separate nucleic acid constructs, e.g., on separate plasmids.Furthermore, any polynucleotide may encode a single polypeptide, e.g., asingle antigen, cytokine, or regulatory polypeptide, or may encode morethan one polypeptide, e.g., a polynucleotide may encode two or morepolypeptides. In addition, a polynucleotide may encode a regulatoryelement such as a promoter or a transcription terminator, or may encodea specific element of a polypeptide or protein, such as a secretorysignal peptide or a functional domain.

Nucleic acids and/or polynucleotides of the present invention, e.g.,plasmid DNA, derivatives of plasmid DNA, mRNA, linear DNA, viralgenomes, or polynucleotide fragments contained therein may be formulatedinto any of the various compositions and may be used in any of themethods disclosed herein. For aqueous compositions used in vivo, use ofsterile pyrogen-free water is preferred. Such formulations will containan effective amount of a polynucleotide together with sodium phosphateas disclosed herein, in order to prepare pharmaceutically acceptablecompositions suitable for optimal administration to a vertebrate.Insoluble polynucleotides may be solubilized in a weak acid or weakbase, and then diluted to the desired volume, for example, with anaqueous solution of the present invention. The pH of the solution may beadjusted as appropriate. In addition, a pharmaceutically acceptableadditive can be used to provide an appropriate osmolarity. Suchadditives are within the purview of one skilled in the art.

The amount of a polynucleotide included in a composition of the presentinvention depends on many factors, including the age and weight of thesubject, the delivery method and route, the type of treatment desired,and the type of polynucleotide being administered. In general, acomposition of the present invention includes from about 1 ng to about30 mg of a polynucleotide, more preferably, from about 100 ng to about10 mg of a polynucleotide.

Certain preferred compositions of the present invention may includeabout 1 ng of a polynucleotide, about 5 ng of a polynucleotide, about 10ng of a polynucleotide, about 50 ng of a polynucleotide, about 100 ng ofa polynucleotide, about 500 ng of a polynucleotide, about 1 μg of apolynucleotide, about 5 μg of a polynucleotide, about 10 μg of apolynucleotide, about 50 μg of a polynucleotide, about 100 μg of apolynucleotide, about 150 μg of a polynucleotide, about 200 μg of apolynucleotide, about 250 μg of a polynucleotide, about 300 μg of apolynucleotide, about 350 μg of a polynucleotide, about 400 μg of apolynucleotide, about 450 μg of a polynucleotide, about 500 μg of apolynucleotide, about 550 μg of a polynucleotide, about 600 μg of apolynucleotide, about 650 μg of a polynucleotide, about 700 μg of apolynucleotide, about 750 μg of a polynucleotide, about 800 μg of apolynucleotide, about 850 μg of a polynucleotide, about 900 μg of apolynucleotide, about 950 μg of a polynucleotide, about 1 mg of apolynucleotide, about 5 mg of a polynucleotide, about 0 mg of apolynucleotide, about 15 mg of a polynucleotide, about 20 mg of apolynucleotide, about 25 mg of a polynucleotide, and about 30 mg of apolynucleotide.

The choice of polynucleotide form depends in part on the desiredkinetics and duration of expression. When long-term expression of thepolypeptide encoded by the polynucleotide is desired, the preferred formis DNA, preferably plasmid DNA. Alternatively, when short-termexpression of the polypeptide encoded by the polynucleotide is desired,the preferred form is RNA, preferably messenger RNA, since RNA israpidly translated into polypeptide, but is degraded more quickly thanDNA.

In one embodiment, a polynucleotide of the present invention is RNA.Preferably in this embodiment, the RNA is in the form of messenger RNA(mRNA). Methods for introducing RNA sequences into vertebrate cells isdescribed in U.S. Pat. No. 5,580,859, the disclosure of which isincorporated herein by reference in its entirety.

Alternatively, the RNA is in the form of an RNA virus genome. Preferablyan RNA virus genome of the present invention is noninfectious. (i.e.,does not result in the production of infectious virus particles invertebrate cells). Suitable RNA virus genomes include, but are notlimited to, alphavirus genomes, picornavirus genomes, and retrovirusgenomes. Methods for the in vivo introduction of non-infectious viralgenomes to vertebrate tissues are well known to those of ordinary skillin the art and are described. e.g., in Altman-Hamamdzic, S., et al.,Gene Therapy 4, 815-822 (1997), in U.S. Pat. No. 4,980,289, Dec. 25,1990, and in Miller, A. D., et al., Meth. Enzymol. 217:581-599 (1993),the disclosures of which are incorporated herein by reference in theirentireties. Viral replicons, i.e., non-infectious RNA virus genomespackaged in a viral coat, e.g., a picornavirus coat or an alphaviruscoat, are also useful for efficient administration of RNA. See, e.g.,U.S. Pat. No. 5,766,602, U.S. Pat. No. 5,614,413, and PCT PublicationNo. WO 95/07994, the disclosures of which are incorporated herein byreference in their entireties.

Preferably, the polynucleotide is DNA. In the case of DNA, apolynucleotide encoding a polypeptide is normally operably associatedwith a promoter. The promoter may be a cell-specific promoter thatdirects substantial transcription of the DNA only in predeterminedcells. Other transcription control elements, besides a promoter, forexample enhancers, operators, repressors, and transcription terminationsignals, can be operably associated with the polynucleotide to directcell-specific transcription.

An operable association is when a polynucleotide encoding a geneproduct, e.g., a polypeptide, is associated with one or more regulatorysequences in such a way as to place expression of the molecule under theinfluence or control of the regulatory sequence(s). Two DNA fragments(such as a polypeptide-coding polynucleotide and a promoter associatedwith the 5′ end of the polynucleotide) are “operably associated ifinduction of promoter function results in the transcription of mRNAencoding the desired gene product and if the nature of the linkagebetween the two DNA fragments does not (1) result in the introduction ofa frame-shift mutation, (2) interfere with the ability of the expressionregulatory sequences to direct the expression of the gene product, or(3) interfere with the ability of the DNA template to be transcribed.Thus, a promoter region would be operably associated with apolynucleotide encoding a polypeptide if the promoter was capable ofeffecting transcription of that polynucleotide.

A variety of transcription control regions are known to those skilled inthe art. Preferred transcription control regions include those whichfunction in vertebrate cells, such as, but not limited to, promoter andenhancer segments from cytomegaloviruses (preferably the immediate earlypromoter, preferably in conjunction with intron-A), simian virus 40(preferably the early promoter), retroviruses (such as Rous sarcomavirus), and picornaviruses (particularly an internal ribosome entrysite, or IRES, also referred to as a CITE sequence). Other preferredtranscription control regions include those derived from vertebrategenes such as actin, heat shock protein, bovine growth hormone andrabbit β-globin, as well as other sequences capable of controlling geneexpression in eukaryotic cells. Additional suitable transcriptioncontrol regions include tissue-specific promoters and enhancers as wellas lymphokine-inducible promoters (e.g., promoters inducible byinterferons or interleukins).

Preferably, a DNA polynucleotide of the present invention is part of acircular or linearized plasmid which is preferably non-infectious (i.e.,does not result in the production of infectious virus particles invertebrate cells), and nonintegrating (i.e., does not integrate into thegenome of vertebrate cells). A linearized plasmid is a plasmid that waspreviously circular but has been linearized, for example, by digestionwith a restriction endonuclease.

Alternatively, DNA virus genomes may be used to administer DNApolynucleotides into vertebrate cells. Preferably a DNA virus genome ofthe present invention is noninfectious, (i.e., does not result in theproduction of infectious virus particles in vertebrate cells), andnonintegrating (i.e., does not integrate into the genome of vertebratecells). Suitable DNA virus genomes include herpesvirus genomes,adenovirus genomes, adeno-associated virus genomes, and poxvirusgenomes. References citing methods for the in vivo introduction ofnon-infectious virus genomes to vertebrate tissues are well known tothose of ordinary skill in the art, and are cited supra.

Polynucleotides of the present invention may be associated withadditional polynucleotides which encode secretory or signal peptides,which direct the secretion of the polypeptide encoded by thepolynucleotide of the present invention. Those of ordinary skill in theart are aware that polypeptides secreted by vertebrate cells normallyhave a signal peptide which is cleaved from the complete polypeptide toproduce a secreted “mature” form of the polypeptide.

Polypeptides

Compositions of the present invention may be used to deliver a widevariety of polypeptides to a vertebrate in need of any givenpolypeptide. Suitable polypeptides include, but are not limited to:therapeutic polypeptides, antigenic polypeptides, immunogenicpolypeptides, immunomodulatory polypeptides, functional selfpolypeptides, and other functional polypeptides.

As used herein, a “therapeutic polypeptide” is a polypeptide which whendelivered to a vertebrate, treats, i.e., cures, ameliorates, or lessensthe symptoms of, a given disease in that vertebrate, or alternatively,prolongs the life of the vertebrate by slowing the progress of aterminal disease. As used herein, an “immunomodulatory polypeptide” is apolypeptide which, when delivered to a vertebrate, can alter, enhance,suppress, or regulate an immune response in a vertebrate.Immunomodulatory polypeptides are a subset of therapeutic polypeptides.Therapeutic and immunomodulatory polypeptides of the present inventioninclude, but are not limited to, cytokines, chemokines, lymphokines,ligands, receptors, hormones, apoptosis-inducing polypeptides, enzymes,antibodies, and growth factors. Examples include, but are not limited togranulocyte macrophage colony stimulating factor (GM-CSF), granulocytecolony stimulating factor (G-CSF), macrophage colony stimulating factor(M-CSF), colony stimulating factor (CSF), interleukin 2 (IL-2),interleukin-3 (IL-3), interleukin 4 (IL-4), interleukin 5 (IL-5),interleukin 6 (IL-6), interleukin 7 (IL-7), interleukin 8 (IL-8),interleukin 10 (IL-10), interleukin 12 (IL-12), interleukin 15 (IL-15),interleukin 18 (IL-18), interferon alpha (IFNα), interferon beta (IFNβ),interferon gamma (IFNγ), interferon omega (IFNω), interferon tau (IFNτ),interferon gamma inducing factor I (IGIF), transforming growth factorbeta (TGF-β), RANTES (regulated upon activation, normal T-cell expressedand presumably secreted), macrophage inflammatory proteins (e.g., MIP-1alpha and MIP-1 beta), Leishmania elongation initiating factor (LEIF),platelet derived growth factor (PDGF), tumor necrosis factor (TNF),growth factors, e.g., epidermal growth factor (EGF), vascularendothelial growth factor (VEGF), fibroblast growth factor, (FGF), nervegrowth factor (NGF), brain derived neurotrophic factor (BDNF),neurotrophin-2 (NT-2), neurotrophin-3 (NT-3), neurotrophin-4 (NT-4),neurotrophin-5 (NT-5), glial cell line-derived neurotrophic factor(GDNF), ciliary neurotrophic factor (CNTF), erythropoietin (EPO), andinsulin.

Therapeutic polypeptides of the present invention may be used to treatdiseases such as Parkinson's disease, cancer, and heart disease. Inaddition, therapeutic polypeptides may be used to treat autoimmunedisorders such as multiple sclerosis; Sjogren's syndrome; sarcoidosis;insulin dependent diabetes mellitus; autoimmune thyroiditis; arthritis(e.g.), osteoarthritis, rheumatoid arthritis, reactive arthritis, andpsoriatic arthritis; ankylosing spondylitis; and scleroderma. Also,therapeutic polypeptides of the present invention can be used to treatacute and chronic inflammatory disorders, to promote wound healing, andto prevent rejection after transplantation of cells, tissues, or organs.

Therapeutic polypeptides of the present invention, for example,=neurotrophic factors (NTFs), may be used to promote the survival,maintenance, differentiation, repair, regeneration, and growth of cellsin the brain, spinal cord, and peripheral nerves. Suitable NTFs include,but are not limited to, NGF, BDNF, the Neurotrophins or NTs such asNT-2, NT-3, NT-4, NT-5, GDNF, CNTF, as well as others. Theadministration of purified recombinant NTFs represents a clinicalstrategy for treatment of such acute and chronic nervous systemdisorders. Such disorders include, but are not limited to mechanical orchemical brain or spinal cord injury, Parkinson's Disease, Alzheimer'sDisease and other dementias, Amyotrophic Lateral Sclerosis and MultipleSclerosis.

Therapeutic polypeptides of the present invention, for example, growthfactors, may be used to promote wound healing. Useful growth factorsinclude, but are not limited to FGF, and EGF.

Therapeutic polypeptides of the present invention may be used to promotecell suicide (termed “apoptosis”). Suitable apoptotic polypeptidesinclude the BAX protein. Alternatively, therapeutic polypeptides of thepresent invention may be used to prevent apoptosis. Suitable apoptosisantagonists include the BAX antagonist Bcl-2. A disease which may betreated with apoptosis-inhibiting polypeptides is Muscular Dystrophy(MD), where patients have a defective protein called Dystrophin.Dystrophin is required for proper muscle function. The non-defective,normal Dystrophin may act as an antigen if delivered via plasmid DNA topatients with MD. In this case, muscle cells transduced with DNAencoding normal Dystrophin would be recognized by the immune system andkilled by Dystrophin-specific T cell based responses. Such T cell basedkilling is known to kill cells by inducing apoptosis. If the normal, andpotentially immunogenic, Dystrophin could be delivered into muscle cellsalong with Bcl-2 or other apoptosis-preventing protein, one would expectthat CTL would be unable to kill the muscle cells. This reasoningapplies to many genetic diseases where treatment involves delivery of a“normal”, and therefore potentially immunogenic, copy of a protein.

As used herein, a “functional self polypeptide” is a polypeptide whichis required for normal functioning of a vertebrate, but because of,e.g., genetic disease, cancer, environmental damage, or other cause, ismissing, defective, or non-functional in a given individual. Acomposition of the present invention is used to restore the individualto a normal state by supplying the necessary polypeptide. Examples offunctional self polypeptides include insulin, dystrophin, cysticfibrosis transmembrane conductance regulator, granulocyte macrophagecolony stimulating factor, granulocyte colony stimulating factor,macrophage colony stimulating factor colony stimulating factor,interleukin 2, interleukin-3, interleukin 4, interleukin 5, interleukin6, interleukin 7, interleukin 8, interleukin 10, interleukin 12,interleukin 15, interleukin 18, interferon alpha, interferon beta,interferon gamma, interferon omega, interferon tau, interferon gammainducing factor I, transforming growth factor beta, RANTES, Flt-3ligand, macrophage inflammatory proteins, platelet derived growthfactor, tumor necrosis factor, epidermal growth factor, vascularepithelial growth factor, fibroblast growth factor, insulin-like growthfactors I and II, insulin-like growth factor binding proteins, nervegrowth factor, brain derived neurotrophic factor, neurotrophin-2,neurotrophin-3, neurotrophin-4, neurotrophin-5, glial cell line-derivedneurotrophic factor, ciliary neurotrophic factor, and erythropoietin.Examples of diseases or disorders that may be treated with functionalself polypeptides include, but are not limited to: diabetes, musculardystrophy, multiple sclerosis, Parkinson's disease, Alzheimer's disease,arthritis, sickle cell anemia, and hemophilia.

As used herein, an antigenic polypeptide or an immunogenic polypeptideis a polypeptide which, when introduced into a vertebrate, reacts withthe immune system molecules of the vertebrate, i.e., is antigenic,and/or induces an immune response in the vertebrate, i.e., isimmunogenic. It is quite likely that an immunogenic polypeptide willalso be antigenic, but an antigenic polypeptide, because of its size orconformation, may not necessarily be immunogenic. Examples of antigenicand immunogenic polypeptides include, but are not limited to,polypeptides from infectious agents such as bacteria, viruses,parasites, or fungi, allergens such as those from pet dander, plants,dust, and other environmental sources, as well as certain selfpolypeptides, for example, tumor-associated antigens.

Antigenic and immunogenic polypeptides of the present invention can beused to prevent or treat, i.e., cure, ameliorate, lessen the severityof, or prevent or reduce contagion of viral, bacterial, fungal, andparasitic infectious diseases, as well as to treat allergies.

In addition, antigenic and immunogenic polypeptides of the presentinvention can be used to prevent or treat, i.e., cure, ameliorate, orlessen the severity of cancer including, but not limited to, cancers oforal cavity and pharynx (i.e., tongue, mouth, pharynx), digestive system(i.e., esophagus, stomach, small intestine, colon, rectum, anus, analcanal, anorectum, liver, gallbladder, pancreas), respiratory system(i.e., larynx, lung), bones, joints, soft tissues (including heart),skin, melanoma, breast, reproductive organs (i.e., cervix, endometrium,ovary, vulva, vagina, prostate, testis, penis), urinary system (i.e.,urinary bladder, kidney, ureter, and other urinary organs), eye, brain,endocrine system (i.e., thyroid and other endocrine), lymphoma (i.e.,hodgkin's disease, non-hodgkin's lymphoma), multiple myeloma, leukemia(i.e., acute lymphocytic leukemia, chronic lymphocytic leukemia, acutemyeloid leukemia, chronic myeloid leukemia).

Examples of viral antigenic and immunogenic polypeptides include, butare not limited to, adenovirus polypeptides, alphavirus polypeptides,calicivirus polypeptides, e.g., a calicivirus capsid antigen,coronavirus polypeptides, distemper virus polypeptides, Ebola viruspolypeptides, enterovirus polypeptides, flavivirus polypeptides,hepatitis virus (AE) polypeptides, e.g., a hepatitis B core or surfaceantigen, herpesvirus polypeptides, e.g., a herpes simplex virus orvaricella zoster virus glycoprotein, immunodeficiency viruspolypeptides, e.g., the human immunodeficiency virus envelope orprotease, infectious peritonitis virus polypeptides, influenza viruspolypeptides, e.g., an influenza A hemagglutinin, neuraminidase, ornucleoprotein, leukemia virus polypeptides, Marburg virus polypeptides,orthomyxovirus polypeptides, papilloma virus polypeptides, parainfluenzavirus polypeptides, e.g., the hemagglutinin/neuraminidase, paramyxoviruspolypeptides, parvovirus polypeptides, pestivirus polypeptides, picornavirus polypeptides, e.g., a poliovirus capsid polypeptide, pox viruspolypeptides, e.g., a vaccinia virus polypeptide, rabies viruspolypeptides, e.g., a rabies virus glycoprotein G, reoviruspolypeptides, retrovirus polypeptides, and rotavirus polypeptides.

Examples of bacterial antigenic and immunogenic polypeptides include,but are not limited to, Actinomyces polypeptides, Bacillus polypeptides,Bacteroides polypeptides, Bordetella polypeptides, Bartonellapolypeptides, Borrelia polypeptides, e.g., B. burgdorferi OspA, Brucellapolypeptides, Camphylobacter polypeptides, Capnocytophaga polypeptides,Chlamydia polypeptides, Clostridium polypeptides, Corynebacteriumpolypeptides, Coxiella polypeptides, Dermatophilus polypeptides,Enterococcus polypeptides, Ehrlichia polypeptides, Escherichiapolypeptides, Francisella polypeptides, Fusobacterium polypeptides,Haemobarionella polypeptides, Haemophilus polypeptides, e.g., H.influenzae type b outer membrane protein, Helicobacter polypeptides,Klebsiella polypeptides. L-form bacteria polypeptides, Leptospirapolypeptides, Listeria polypeptides, Mycobacteria polypeptides,Mycoplasma polypeptides, Neisseria polypeptides, Neorickettsiapolypeptides, Nocardia polypeptides, Pasteurella polypeptides,Peptococcus polypeptides, Peptostreptococcus polypeptides, Pneumococcuspolypeptides, Proteus polypeptides, Pseudomonas polypeptides, Rickettsiapolypeptides, Rochalimaea polypeptides, Salmonella polypeptides,Shigella polypeptides, Staphylococcus polypeptides, Streptococcuspolypeptides, e.g., S. pyogenes M proteins, Treponema polypeptides, andYersinia polypeptides, e.g., Y. pestis F1 and V antigens.

Examples of fungal immunogenic and antigenic polypeptides include, butare not limited to, Absidia polypeptides, Acremonium polypeptides.Alternaria polypeptides, Aspergillus polypeptides, Basidioboluspolypeptides, Bipolaris polypeptides, Blastomyces polypeptides, Candidapolypeptides, Coccidioides polypeptides, Conidiobolus polypeptides,Cryptococcus polypeptides, Curvalaria polypeptides, Epidermophytonpolypeptides, Exophiala polypeptides, Geotrichum polypeptides,Histoplasma polypeptides, Madurella polypeptides, Malasseziapolypeptides, Microsporum polypeptides, Moniliella polypeptides,Mortierella polypeptides, Mucor polypeptides, Paecilomyces polypeptides,Penicillium polypeptides, Phialemonium polypeptides, Phialophorapolypeptides, Prototheca polypeptides, Pseudallescheria polypeptides,Pseudomicrodochium polypeptides, Pythium polypeptides, Rhinosporidiumpolypeptides, Rhizopus polypeptides, Scolecobasidium polypeptides,Sporothrix polypeptides, Stemphylium polypeptides, Trichophytonpolypeptides, Trichosporon polypeptides, and Xylohypha polypeptides.

Examples of protozoan parasite immunogenic and antigenic polypeptidesinclude, but are not limited to, Babesia polypeptides, Balantidiumpolypeptides, Besnoitia polypeptides, Cryptosporidium polypeptides,Eimeria polypeptides, Encephalitozoon polypeptides, Entamoebapolypeptides, Giardia polypeptides, Hammondia polypeptides, Hepatozoonpolypeptides, Isospora polypeptides, Leishmania polypeptides,Microsporidia polypeptides, Neospora polypeptides, Nosema polypeptides,Pentatrichomonas polypeptides, Plasmodium polypeptides, e.g. P.falciparum circumsporozoite (PfCSP), sporozoite surface protein 2(PfLSP2), carboxyl terminus of liver state antigen 1 (PfLSA1 c-term),and exported protein 1 (PfExp-1), Pneumocystis polypeptides, Sarcocystispolypeptides, Schistosoma polypeptides, Theileria polypeptides,Toxoplasma polypeptides, and Trypanosoma polypeptides.

Examples of helminth parasite immunogenic and antigenic polypeptidesinclude, but are not limited to, Acanthocheilonema polypeptides,Aelurostrongylus polypeptides, Ancylostoma polypeptides, Angiostrongyluspolypeptides, Ascaris polypeptides, Brugia polypeptides, Bunostomumpolypeptides, Capillaria polypeptides, Chabertia polypeptides, Cooperiapolypeptides, Crenosoma polypeptides, Dictyocaulus polypeptides,Dioctophyme polypeptides, Dipetalonema polypeptides, Diphyllobothriumpolypeptides, Diplydium polypeptides, Dirofilaria polypeptides,Dracunculus polypeptides, Enterobius polypeptides, Filaroidespolypeptides, Haemonchzis polypeptides, Lagochilascaris polypeptides,Loa polypeptides, Mansonella polypeptides, Muellerius polypeptides,Nanophyetus polypeptides, Necator polypeptides, Nematodiruspolypeptides, Oesophagostomum polypeptides, Onchocerca polypeptides,Opisthorchis polypeptides, Ostertagia polypeptides, Parafilariapolypeptides, Paragonimus polypeptides, Parascaris polypeptides,Physaloptera polypeptides, Prolostrongylus polypeptides, Setariapolypeptides, Spirocerca polypeptides Spirometra polypeptides,Stephanofilaria polypeptides, Strongyloides polypeptides, Strongyluspolypeptides, Thelazia polypeptides, Toxascaris polypeptides, Toxocarapolypeptides, Trichinella polypeptides, Trichostrongylus polypeptides,Trichuris polypeptides, Uncinaria polypeptides, and Wuchereriapolypeptides.

Examples of ectoparasite immunogenic and antigenic polypeptides include,but are not limited to, polypeptides (including protective antigens aswell as allergens) from fleas; ticks, including hard ticks and softticks; flies, such as midges, mosquitoes, sand flies, black flies, horseflies, horn flies, deer flies, tsetse flies, stable flies,myiasis-causing flies and biting gnats, ants; spiders, lice; mites; andtrue bugs, such as bed bugs and kissing bugs.

Examples of tumor-associated antigenic and immunogenic polypeptidesinclude, but are not limited to, tumor-specific immunoglobulin variableregions (e.g., B cell lymphoma idiotypes), GM2, Tn, sTn,Thompson-Friedenreich antigen (TF), Globo H, Le(y), MUC1, MUC2, MUC3.MUC4, MUC5AC, MUC5B, MUC7, carcinoembryonic antigens, beta chain ofhuman chorionic gonadotropin (hCG beta), HER2/neu, PSMA, EGFRvIII, KSA,PSA, PSCA, GP100, MAGE 1, MAGE 2, TRP 1, TRP 2, tyrosinase. MART-1, PAP,CEA, BAGE, MAGE, RAGE, and related proteins.

Also included as polypeptides of the present invention are fragments,derivatives, analogs, or variants of the foregoing polypeptides, and anycombination of the foregoing polypeptides. Additional polypeptides maybe found, for example in “Foundations in Microbiology,” Talaro, et al.,eds., McGraw-Hill Companies (October 1998), Fields, et al., “Virology,”3d ed., Lippincott-Raven (1996), “Biochemistry and Molecular Biology ofParasites,” Marr, et al., eds., Academic Press (1995), and Deacon,J.,”Modern Mycology,” Blackwell Science Inc (1997), which areincorporated herein by reference.

Transfection Facilitating Materials

Compositions of the present invention can also include one or moretransfection facilitating materials that facilitate delivery ofpolynucleotides to the interior of a cell, and/or to a desired locationwithin a cell. Examples of the transfection facilitating materialsinclude, but are not limited to lipids, preferably cationic lipids;inorganic materials such as calcium phosphate, alum (aluminum sulfate),and metal (e.g., gold or tungsten) particles (e.g., “powder” typedelivery solutions); peptides, including cationic peptides, targetingpeptides for selective delivery to certain cells or intracellularorganelles such as the nucleus or nucleolus, and amphipathic peptides,i.e. helix forming or pore forming peptides; basic proteins, such ashistones; asialoproteins; viral proteins (e.g., Sendai virus coatprotein); pore-forming proteins; and polymers, including dendrimers,star-polymers, “homogenous” poly-amino acids (e.g., poly-lysine,poly-arginine), “heterogenous” poly-amino acids (e.g., mixtures oflysine & glycine), co-polymers, polyvinylpyrrolidinone (PVP), andpolyethylene glycol (PEG). Furthermore, those auxiliary agents of thepresent invention which facilitate and enhance the entry of apolynucleotide into vertebrate cells in vivo, may also be considered“transfection facilitating materials.”

Certain embodiments of the present invention may include lipids as atransfection facilitating material, including cationic lipids (e.g.,DMRIE, DOSPA, DC-Chol. GAP-DLRIE), basic lipids (e.g., steryl amine),neutral lipids (e.g., cholesterol), anionic lipids (e.g., phosphatidylserine), and zwitterionic lipids (e.g., DOPE, DOPC), as described above.However, certain compositions and methods of the present invention,e.g., those including or utilizing compositions comprising a sodiumphosphate dissolved in an aqueous solution at a molar concentration fromabout 20 mM to about 300 mM, are preferably substantially free ofcationic lipids.

Certain other compositions and methods of the present invention, e.g.,those including or utilizing compositions comprising a sodium phosphatedissolved in aqeuous solution at a molar concentration from about 0.1 mMto about 150 mM, where the aqueous solution is substantially free ofchloride anion, always include cationic lipids as transfectionfacilitating agents. While not being bound by theory, cationic lipidsare believed to bind effectively to negatively charged polynucleotides,thereby facilitating entry of the polynucleotide into cells. The use ofcationic lipids is especially effective in the delivery ofpolynucleotides to non-muscle tissues, e.g., pulmonary tissues, tumortissues, skin, peritoneum, tissues of digestive system, or vasculartissues.

In the embodiments including cationic lipids, the polynucleotideconstruct(s) are combined with lipids by mixing, for example, a plasmidDNA solution and a solution of cationic lipid:co-lipid liposomes.Preferably, the concentration of each of the constituent solutions isadjusted prior to mixing such that the desired final plasmidDNA/cationic lipid:co-lipid ratio and the desired plasmid DNA finalconcentration will be obtained upon mixing the two solutions. Forexample, if the desired final solution is to be 150 mM sodium phosphate,the various components of the composition, e.g., plasmid DNA, cationiclipid:co-lipid liposomes, and any other desired auxiliary agents,transfection facilitating materials, or additives are each prepared in110 mM sodium phosphate and then simply mixed to afford the desiredcomplex.

Alternatively, if the desired final solution is to be, e.g., 150 mMsodium phosphate, certain components of the composition, e.g., theauxiliary agent and/or cationic lipid:co-lipid liposomes, is prepared ina volume of water which is less than that of the final volume of thecomposition, and certain other components of the composition, e.g., theplasmid DNA, is prepared in a solution of sodium phosphate at a higherconcentration than 150 mM, in a volume such that when the components inwater are added to the components in the sodium phosphate solution, thefinal composition is in an aqueous solution of 150 mM sodium phosphate.For example, the plasmid DNA could be prepared in 300 mM sodiumphosphate at one half the final volume, the auxiliary agent and/orcationic lipid:co-lipid liposome is prepared in water at one half thefinal volume, and then these two elements are mixed together to producethe final composition.

The cationic lipid:co-lipid liposomes are preferably prepared byhydrating a thin film of the mixed lipid materials in an appropriatevolume of aqueous solvent by vortex mixing at ambient temperatures forabout 1 minute. The thin films are prepared by admixing chloroformsolutions of the individual components to afford a desired molar soluteratio followed by aliquoting the desired volume of the solutions into asuitable container. The solvent is removed by evaporation, first with astream of dry, inert gas (e.g. argon) followed by high vacuum treatment.

A transfection facilitating material can be used alone or in combinationwith one or more other transfection facilitating materials. Two or moretransfection facilitating materials can be combined by chemical bonding(e.g., covalent and ionic such as in lipidated polylysine, PEGylatedpolylysine) (Toncheva, V., et al., Biochim. Biophys. Acta1380(3):354-368 (1998)), mechanical mixing (e.g., free moving materialsin liquid or solid phase such as polylysine+cationic lipids”) (Gao, X.,and Huang, L., Biochemistry 35:1027-1036 (1996); Trubetskoy, V. S., etal., Biochem. Biophys. Acta 1131:311-313 (1992)), and aggregation (e.g.,co-precipitation, gel forming such as in cationic lipids+poly-lactideco-galactide, and polylysine+gelatin).

Other Additives

Other hydrophobic and amphiphilic additives, such as, for example,sterols, fatty acids, gangliosides, glycolipids, lipopeptides,liposaccharides, neobees, niosomes, prostaglandins and sphingolipids,may also be included in the compositions of the present invention. Insuch compositions, these additives may be included in an amount betweenabout 0.1 mol % and about 99.9 mol % (relative to total lipid).Preferably, these additives comprise about 1-50 mol % and, mostpreferably, about 2-25 mol %. Preferred additives include lipopeptides,liposaccharides and steroids.

Methods and Administration

The present invention further provides methods for delivering apolypeptide into a vertebrate, which comprise administering to thevertebrate a composition as described herein; such that uponadministration of the composition, the polypeptide is expressed in thevertebrate, in an amount sufficient to be detectable. Methods to detectpolypeptides expressed in a vertebrate are well known to those ofordinary skill in the art and include, but are not limited to,serological methods to detect the polypeptide in serum, e.g., westernblotting, staining tissue sections by immunohistochemical methods,measuring an immune response generated by the vertebrate against thepolypeptide, and measuring the activity of the polypeptide. Certain ofthese methods are disclosed in the Examples, below.

The present invention further provides a method for delivering atherapeutic polypeptide into a vertebrate, comprising administering to avertebrate in need of the therapeutic polypeptide a composition asdescribed herein. In this method, the composition comprises apolynucleotide encoding a therapeutic polypeptide. Upon administrationof the composition according to this method, the needed therapeuticpolypeptide is expressed in the vertebrate in a therapeuticallyeffective amount.

Similarly, the present invention provides a method of enhancing ormodulating an immune response in a vertebrate in need of such anenhanced or modulated immune response, comprising administering to thevertebrate a composition as described herein. In this method, thecomposition contains a polynucleotide encoding an immunogenic and/orimmunomodulatory polypeptide. Upon administration of the compositionaccording to this method, the needed immunogenic and/or immunomodulatorypolypeptide is expressed in the vertebrate, in a sufficient amount toinduce and/or modify a desired immune response in the vertebrate toprevent disease, cure disease, reduce the severity of disease symptoms,or prolong the life of the vertebrate.

Also, the present invention provides a method of enhancing or modulatingan immune response in a healthy vertebrate for large-scale antibodyproduction, comprising administering to the vertebrate a composition asdescribed herein. In this method, the composition contains apolynucleotide encoding an immunogenic and/or immunomodulatorypolypeptide. Upon administration of the composition according to thismethod, the immunogenic and/or immunomodulatory polypeptide is expressedin the vertebrate, in a sufficient amount to produce a vigorous antibodyresponse in the vertebrate. The antibodies thus produced are thenrecovered from the vertebrate by, for example, the collection of serum,milk, or saliva. Such antibodies may be useful for research ordiagnostic purposes, or for additional therapies in vertebrates in needof such therapies. For example, passive antibody treatment usingantibodies produced by this method may prevent disease, cure disease,reduce the severity of disease symptoms, or prolong the life of avertebrate.

Moreover, the present invention further provides a method of deliveringa physiologically or metabolically necessary polypeptide to a vertebrateincapable of making a functional form of the polypeptide, comprisingadministering to the vertebrate a composition as disclosed herein.According to this method, the composition contains a polynucleotideencoding a functional self polypeptide. Upon administration of thecomposition according to this method, the needed functional selfpolypeptide is expressed in the vertebrate, in a sufficient amount tosupply the vertebrate's requirements for the polypeptide.

An important aspect of the present invention is that use of the claimedcompositions in any of the above methods allows the skilled artisan toreduce the amount of polynucleotide included in the composition relativeto methods utilizing existing compositions, e.g., those which formulatethe polynucleotide in saline or water. Even though the amount ofpolynucleotide is reduced, sufficient protein expression occurs in thetreated vertebrate. Such a reduction in polynucleotide willsignificantly reduce the cost of producing compositions of the presentinvention. Accordingly, one embodiment of the present invention is amethod to reduce the amount of polynucleotide required to obtain adesired clinical response in a vertebrate, comprising administering tothe vertebrate a composition as disclosed herein.

In any of the methods disclosed herein, it is preferred that thecomposition be delivered to a mammal. More preferably, the mammal is ahuman.

Administration of the compositions of the present invention according toany of the above methods can be accomplished according to any of variousmethods known in the art. For example, U.S. Pat. No. 5,676,954,incorporated herein by reference in its entirety, reports on theinjection of genetic material, complexed with cationic lipid carriers,into mice. Also, U.S. Pat. Nos. 5,589,466, 5,693,622, 5,580,859,5,703,055, and PCT international patent application PCT/US94/06069 (WO94/29469), the disclosures of which are incorporated herein by referencein their entireties, provide methods for delivering compositionscomprising naked DNA, or DNA cationic lipid complexes to vertebrates.

More specifically, the compositions of the present invention may beadministered to any tissue of a vertebrate, including, but not limitedto, muscle, skin, brain tissue, lung tissue, liver tissue, spleentissue, bone marrow tissue, thymus tissue, heart tissue, e.g.,myocardium, endocardium, and pericardium, lymph tissue, blood tissue,bone tissue, pancreas tissue, kidney tissue, gall bladder tissue,stomach tissue, intestinal tissue, testicular tissue, ovarian tissue,uterine tissue, vaginal tissue rectal tissue, nervous system tissue, eyetissue, glandular tissue, tongue tissue, and connective tissue, e.g.,cartilage.

Furthermore, the compositions of the present invention may beadministered to any internal cavity of a vertebrate, including, but notlimited to, the lungs, the mouth, the nasal cavity, the stomach, theperitoneal cavity, the intestine, any heart chamber, veins, arteries,capillaries, lymphatic cavities, the uterine cavity, the vaginal cavity,the rectal cavity, joint cavities, ventricles in brain, spinal canal inspinal cord, and the ocular cavities.

Preferably, the compositions comprising sodium phosphate dissolved inaqueous solution at a molar concentration from about 20 mM to about 300mM are delivered to muscle, either skeletal muscle or cardiac muscle,and those embodiments comprising sodium phosphate dissolved in aqueoussolution at a molar concentration from about 0.1 mM to about 150 mM anda cationic lipid are administered to lung tissue. Preferred modes foradministration to lung tissue are disclosed in Wheeler, C. J., et al.,Proc. Natl. Acad. Sci. USA 93:11454-11459 (1996), which is incorporatedherein by reference in its entirety.

According to the disclosed methods, compositions of the presentinvention are preferably administered by intramuscular (i.m.),subcutaneous (s.c.), or intrapulmonary routes. Other suitable routes ofadministration include intratracheal, transdermal, interdermal,intraocular, intranasal, inhalation, transmucosal (i.e., across a mucousmembrane), intracavity (e.g., oral, vaginal, rectal, nasal, peritoneal,ventricular, or intestinal), and intravenous (i.v.) administration.

Any mode of administration can be used so long as the mode results inthe expression of the desired peptide or protein, in the desired tissue,in an amount sufficient to be detectable, and/or prophylactically ortherapeutically effective. Administration means of the present inventioninclude needle injection, catheter infusion, biolistic injectors,particle accelerators (e.g., “gene guns” or pneumatic “needleless”injectors) Med-E-Jet (Vahlsing, H., et al., J. Immunol. Methods 171,11-22 (1994)), Pigjet (Schrijver, R., et al., Vaccine 15, 1908-1916(1997)), Biojector (Davis, H., et al., Vaccine 12, 1503-1509 (1994);Gramzinski. R., et al., Mol. Med. 4, 109-118 (1998)), AdvantaJet(Linmayer, I., et al. Diabetes Care 9:294-297 (1986)), Medi-jector(Martins. J., and Roedl, E. J. Occup. Med. 21:821-824 (1979)), gelfoamsponge depots, other commercially available depot materials (e.g.,hydrogels), osmotic pumps (e.g., Alza minipumps), oral or suppositorialsolid (tablet or pill) pharmaceutical formulations, topical skin creams,and decanting, use of polynucleotide coated suture (Qin, Y., et al.,Life Sciences 65, 2193-2203 (1999)) or topical applications duringsurgery. The preferred modes of administration are intramuscularneedle-based injection and pulmonary application via catheter infusion.Each of the references cited in this paragraph is incorporated herein byreference in its entirety.

Determining an effective amount of a composition depends upon a numberof factors including, for example, the chemical structure and biologicalactivity of the substance, the age and weight of the subject, theprecise condition requiring treatment and its severity, and the route ofadministration. Based on the above factors, determining the preciseamount, number of doses, and timing of doses are within the ordinaryskill in the art and will be readily determined by the attendingphysician or veterinarian.

Compositions of the present invention can be formulated according toknown methods. Suitable preparation methods are described, for example,in Remington's Pharmaceutical Sciences, 16^(th) Edition, A. Osol, ed.Mack Publishing Co., Easton, Pa. (1980), and Remington's PharmaceuticalSciences, 9^(th) Edition, A. R. Gennaro, ed., Mack Publishing Co.,Easton, Pa. (1995), both of which are incorporated herein by referencein their entireties. Although the composition is preferably administeredas an aqueous solution, it can be formulated as an emulsion, gel,solution, suspension, lyophilized form, or any other form known in theart. According to the present invention, if the composition isformulated other than as an aqueous solution, it will requireresuspension in an aqueous solution prior to administration. Inaddition, the composition may contain pharmaceutically acceptableadditives including, for example, diluents, binders, stabilizers, andpreservatives.

For aqueous compositions used in vivo, the use of sterile pyrogen-freewater is preferred. Such formulations will contain an effective amountof a polynucleotide together with a suitable amount of an aqueoussolution in order to prepare pharmaceutically acceptable compositionssuitable for administration to a vertebrate

Pharmaceutical Kits

The present invention also provides kits for use in delivering apolypeptide to a vertebrate. Each kit includes a container holding about1 ng to about 30 mg of a polynucleotide which operably encodes apolypeptide within vertebrate cells in vivo. Furthermore, each kitincludes either (a) an amount of sodium phosphate which, when dissolvedin a prescribed volume of distilled water, results in an aqueoussolution with a molar concentration of said salt from about 20 mM toabout 300 mM, and reaction, association, or dissociation productsthereof; and optionally, an administration means; whereby thepolynucleotide is provided in a prophylactically or therapeuticallyeffective amount to treat a vertebrate; or (b) an amount of sodiumphosphate which, when dissolved in an prescribed volume of distilledwater, results in an aqueous solution with a molar concentration of saidsalt from about 0.1 mM to about 150 mM, and reaction, association, ordissociation products thereof, and where the aqueous solution formedthereby is essentially free of chloride anion; a cationic lipid; andoptionally, an administration means; whereby the polynucleotide isprovided in a prophylactically or therapeutically effective amount. Anyof the components of pharmaceutical kits (a) or (b) can be provided in asingle container or in multiple containers. Preferably, the kit includesfrom about 1 ng to about 30 mg of a polynucleotide, more preferably, thekit includes from about 100 ng to about 10 mg of a polynucleotide.

Any suitable container or containers may be used with pharmaceuticalkits. Examples of containers include, but are not limited to, glasscontainers, plastic containers, or strips of plastic or paper.

Each of the pharmaceutical kits may further comprise an administrationmeans. Means for administration include, but are not limited to syringesand needles, catheters, biolistic injectors, particle accelerators,i.e., “gene guns,” pneumatic “needleless” injectors, gelfoam spongedepots, other commercially available depot materials, e.g., hydrogels,osmotic pumps, and decanting, polynucleotide coated sutures, skinpatches, or topical applications during surgery.

The kit can further comprise an instruction sheet for administration ofthe composition to a vertebrate. The polynucleotide components of thecomposition are preferably provided as a liquid solution or they may beprovided in lyophilized form as a dried powder or a cake. If thepolynucleotide is provided in lyophilized form, the dried powder or cakemay also include any salts, auxiliary agents, transfection facilitatingagents, and additives of the composition in dried form. Such a kit mayfurther comprise a container with an exact amount of sterilepyrogen-free water, for precise reconstitution of the lyophilizedcomponents of the composition.

The container in which the composition is packaged prior to use cancomprise a hermetically sealed container enclosing an amount of thelyophilized formulation or a solution containing the formulationsuitable for a pharmaceutically effective dose thereof, or multiples ofan effective dose. The composition is packaged in a sterile container,and the hermetically sealed container is designed to preserve sterilityof the pharmaceutical formulation until use. Optionally, the containercan be associated with administration means and/or instruction for use.

EXAMPLES

Having now generally described the invention, the same will become morereadily understood by reference to the following specific examples whichare included herein for purposes of illustration only and are notintended to be limiting unless otherwise specified.

Described herein are: 1) the in vitro characterization of biologicalactivities of and IFNs delivered by plasmid DNA (anti-proliferativeactivity and anti-viral activity in vitro); 2) in vivo expression ofcytokines following in vivo administration of cytokine-expressing pDNA;and 3) the in vivo characterization of anti-tumor activity of cytokinesin murine models of solid and metastatic tumors following intratumoral,intramuscular or intra-cavity administration of cytokine-encoding pDNA.

The cytokine-encoding polynucleotide constructs have potentanti-proliferative activity in vitro. Moreover, the in vivo anti-tumoractivities of IFNω, IFNα, IL-2, and IL-12 are herein demonstrated inmultiple murine tumor models including nude mice bearing subcutaneoushuman tumors, or in immunocompetent mice bearing murine solid andmetastatic tumors. Intratumoral, intramuscular, or intraperitonealinjection of the cytokine-encoding plasmids is shown to result in astatistically significant slowing of tumor growth and/or a statisticallysignificant increase in survival. In addition to the potent antitumoreffects of the cytokine plasmids delivered via intratumoral orintramuscular injection, this is the first in vivo demonstration ofanti-tumor activity for human interferon-ω. Moreover, the in vivoantitumor activity of IL-2 in the treatment of peritoneally disseminatedcancers, such as ovarian metastatic melanoma is also demonstrated.

Example 1 Construction of Expression Vectors

Three basic eukaryotic expression plasmid vectors, termed VR1012, VR1055and VR1033 were used in the construction of all plasmids used in thefollowing examples. The blank plasmids, VR1012 and VR1055 differ only intranscriptional termination sequences. The backbone of both plasmids isderived from pUC19, with the beta-lactamase (ampicillin resistance) genereplaced by the aminoglycoside acetyltransferase (kanamycin resistance)gene from pET9a (Novagen, Madison, Wis.). Both plasmids directeukaryotic gene expression from a cassette containing the humancytomegalovirus immediate early I (CMV IE) gene promoter/enhancer, CMVIE 5′ untranslated (UT) sequence, and intron A. Following theseregulatory elements is a cloning polylinker for insertion of polypeptidecoding sequences. Following the polylinker in VR1012 is the 3′ UTsequence from the bovine growth hormone gene for polyadenylation andtranscriptional termination. In VR1055, the transcriptional terminatorregion includes a polyadenylation and termination signals derived fromthe rabbit b-globin gene. VR1033 is identical to VR1012, except that itcontains a cap-independent translational enhancer from theencephalomyocarditis virus within the cloning polylinker sequence. Thissequence allows the production of two different polypeptides from asingle expressed mRNA.

Plasmid VR4101 (murine interferon α (mIFNα)) was constructed by cloningthe murine interferon α cDNA into the vector VR1012 vector. The cDNA wasobtained by amplifying the coding sequence from the plasmid RSV-″1(Kelly, K. A. and P. M. Pitha, Nucl. Acids Res. 13: 805-823 (1985);Kelly, K. A. and P. M. Pitha, Nucl. Acids Res. 13: 825-839 (1985)),which was provided by Dr. Paula Pitha-Rowe of Johns Hopkins University.Plasmid VR4111 was constructed by transferring the coding sequences fromVR4101 to the VR1055 cloning vector. The oligonucleotide primers usedfor polymerase chain reaction (PCR) were5′-AACTGCAGATGGCTAGGCTCTGTGCT-3′ (SEQ ID No. 15) and5′-GAAG-ATCTTCATTTCTCTTCTC-TCAG-3′ (SEQ ID No. 16). Reaction conditionswere 30 cycles of 94° C. for 1 minute (denaturing), 58° C. for 2 minutes(annealing), and 72° C. for 1 minute (extension).

Plasmid VR4102 (human interferon α (hIFNα)) was constructed by cloningthe human interferon of cDNA into the VR1012 vector. The cDNA wasobtained by amplifying the coding sequence from human genomic DNAprepared from a fresh blood sample. Plasmid VR4112 was constructed bytransferring the coding sequence sequences from VR4102 to the VR1055cloning vector. Genomic DNA was isolated using the QIAamp Blood Kit(Qiagen, Inc.). The oligonucleotide primers used for PCR were5′-AACTGCAGATGGCCTC-GCCCTTTGCT-3′ (SEQ ID No. 17) and5′-CGGGATCCTTATTCCTTC-CTCCTTAATC-3′ (SEQ ID No. 18). Reaction conditionswere 30 cycles of 94^(B)C for 1 minute (denaturing), 58° C. for 2minutes (annealing), and 72° C. for 1 minute (extension).

Plasmid VR4150 (human interferon ω (hIFNω)) was constructed by cloningthe human IFNω cDNA into the VR1012 cloning vector. The cDNA wasobtained by amplifying the coding sequence from human genomic DNAprepared from a fresh blood sample. Plasmid VR4151 (SEQ ID No. 1) wasconstructed by transferring the coding sequences from VR4150 to theVR1055 cloning vector. The oligonucleotide primers used for PCR were5′-GCTCTAGATGGCCCTCCTGTTCCCT-3′ (SEQ ID No. 19) and5′-GCGG-ATCCTCAAGATGAGCCCAGGTC-3′ (SEQ ID No. 20). Reaction conditionswere 30 cycles of 94° C. for 1 minute (denaturing), 58° C. for 2 minutes(annealing), and 72° C. for 1 minute (extension).

Plasmid VR1110 (murine interleukin-2 (mIL-2)) was constructed by cloningmodified murine IL-2 cDNA into the VR1012 vector. The 5′ UT sequence andthe two amino acids of the leader peptide were replaced with the ratinsulin II gene 5′ UT sequence and coding region of the first six aminoacids of the rat preproinsulin leader peptide. The IL-2 cDNA was thencloned into the BamHI site of VR1012.

Plasmid VR1103 (human interleukin-2 (hIL-2)) is identical to VR1110 withthe exception that the murine IL-2 cDNA was replaced with the cDNA forhuman IL-2 (Parker et. al. 1996).

Plasmid VR4001 (murine interleukin-12 (mIL-12)) was constructed bycloning the cDNA's encoding the two murine subunits p35 and p40 into theVR1033 vector. Both cDNA's were obtained by amplifying the codingsequences from plasmids provided by Dr. Thomas Gajewski of TheUniversity of Chicago (J. Immun., 154:5637; J. Immun., 156:1095). Theoligonucleotides used for PCR of p35 were 5′-CAT GCC ATG GGT CAA TCA CGCTAC CTC CTC TTT TTG G-3′ (SEQ ID No. 23) and 5′-GCG GAT CCT CAG GCG GAGCTC AGA TAG CCC-3′ (SEQ ID No. 24). The oligonucleotides used for PCR ofp40 were 5′-ACG CGT CGA CAT GTG TCC TCA GAA GCT AAC CAT CTC-3′ (SEQ IDNo. 21) and 5′-GCG GAT CCC TAG GAT CGG ACC CTG CAG GGA ACA C-3′ (SEQ IDNo. 22). Reaction conditions were 30 cycles of 94° C. for 1 minute(denaturing), 58° C. for 2 minutes (annealing), and 72° C. for 1 minute(extension).

Plasmids VR1223 (luciferase) was constructed by cloning cytoplasmicluciferase gene into the VR1012 vector (Hartikka et al. Hum. Gene Ther.7:1205-1217, 1996). The source of the cytoplasmic luciferase gene foundin VR1223 was the plasmid termed pSP-luc+which was purchased fromPromega. An Avr II-Xba I restriction fragment encoding the luciferasecDNA was transferred from pSP-luc+ to VR1012 to make VR1223.

Plasmid VR1412 (β-galactosidase) was constructed by cloning cytoplasmicβ-gal gene into the VR1012 vector (Doh et al., Gene Ther. 4:648-663).

Plasmid VR1332 was constructed by inserting a SalI-BamHI fragmentencoding chloramphenicol acetyltransferase (CAT) from pBS-CAT (Promega)into SalI/BamHI-cut VR1012 vector (Hartikka et al., Hum. Gene Ther.7:1205-1217 (1996)).

Example 2 Purification of pDNA

pDNA was transformed into Escherichia coli DH10B-competent cells andgrown in Terrific Broth (Sambrook, J. et al., in: Molecular Cloning: Alaboratory manual, Cold Spring Harbor Laboratory Press, Cold SpringHarbor, N.Y., p. A.2 (1989)) complemented with 50 μg/ml kanamycin in a 1Liter shaker flask. Cells were harvested by centrifugation at the end ofthe exponential growth phase (approximately 16 hr), typically yielding10 grams of biomass net weight per liter. Covalently closed circularpDNA was isolated by a modified lysis procedure (Horn, N. A. et al.,Human Gene Therapy 6: 565-573 (1995)) followed by standard doubleCsCl-ethidium bromide gradient ultracentrifugation with an average yieldof approximately 5 mg per liter. Plasmids were ethanol precipitated andresolubilized in saline at 4° C. and dialyzed against saline. Endotoxincontent was determined by the Limulus Amebocyte Lysate assay (Associatesof Cape Cod, Inc., Falmouth, Mass.). All plasmid preparations were freeof detectable RNA. Endotoxin levels were less than 0.6 EndotoxinUnits/μg of plasmid DNA. The spectrophotometric A260/A280 ratios werebetween 1.75 and 2.0.

Example 3 In Vitro Evaluation of Biological Activity of IFNω and IFNα

To assure that the interferon plasmid DNA used in the following examplesencoded biologically active interferon, cell proliferation and antiviralassays were performed. All culture medium used in this and followingexamples was obtained from Life Technologies (Gaithersburg, Md.), andall serum was obtained from HyClone (Logan, Utah).

UM449 cells (American Type Culture Collection, Rockville, Md.) wereplated at a concentration of 2×10⁵ cells per well in a 6 well plate andincubated for 24 hours. Plasmid DNA and the lipid, DMRIE/DOPE (1:1) wereeach diluted to a concentration of 1 mg in 0.5 ml Optimem medium (LifeTechnologies, Gaithersburg, Md.). The lipid DMRIE/DOPE consists of thecationic lipid(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propanaminiumbromide (DMRIE) and the neutral lipid dioleoylphosphatidylethanolamine(DOPE) at a 1:1 mol:mol ratio (Felgner et al., J. Biol. Chem.269:2550-2561, 1994). DMRIE/DOPE has been shown to be effective for bothin vitro (Felgner et al., J. Biol. Chem. 269:2550-2561, 1994) and invivo transfection (Stopeck et al., J. Clin. Oncol. 15:341-349, 1997 andRubin et al., Gene Ther. 4:419-425, 1997). The lipid mixture and the DNAmixture were then gently mixed. Medium was removed from the cells whichwere rinsed gently with PBS, followed by addition of the DNA:lipidmixture (1 ml/well). After incubating the cells for 4-5 h at 37° C., oneml of Optimem with 30% fetal calf serum (FCS) was added to each well.Following an overnight incubation at 37° C., one ml of Optimem with 10%FCS was added to each well. Tissue culture supernatants were collected48 h after the start of the in vitro transfection.

a. Antiproliferative Activity

To evaluate the antiproliferative and hence, anti-tumor activity of IFNωand IFNα, supernatants from the above described UM449 cells transfectedwith the interferon or control plasmid DNA were tested in a cellproliferation assay of murine or human tumor cell lines (ATCC,Rockville, Md.) using the Boehringer Mannheim (Indianapolis, Ind.) CellProliferation Kit II (XTT). Murine or human tumor cells were plated in96 well plates at the desired concentration (cell concentration variedwith each cell line evaluated, for example, at a concentration of 5×10³cells/ml for B16F10 cells and 5×10⁴ cells/ml for the Cloudman S91 andglioma 261 cells). The plates were incubated at 37° C. for 24 hoursfollowed by addition of tissue culture supernatants from UM449 cells invitro transfected with either interferon plasmid DNA or control plasmidDNA. As a positive control for mIFNα plasmid DNA, mIFNα protein (ICNPharmaceuticals Inc., Costa Mesa, Calif.) was serially diluted and addedto the wells. For the hIFN plasmid DNA, an interferon reference standard(human leukocyte interferon, Sigma Chemical Co., St. Louis, Mo.) wasincluded in each assay. Following a 24-72 hour incubation, at 37° C., 50μl of XTT/ECR substrate was added to each well. Plates were incubatedfor 6-24 hours at 37° C. and the optical density (OD) at 490 nm wasdetermined. Increasing amounts of interferon result in inhibition ofcell proliferation and a reduction in the OD₄₉₀. The percent reductionin cell proliferation due to addition of the supernatants was determinedby the formula:

$1 - {\frac{{OD}_{490}}{{OD}_{490}}\frac{\mspace{56mu}{{{of}\mspace{14mu}{cells}\mspace{20mu}{incubated}\mspace{20mu}{with}}\mspace{11mu}{{interferon}\mspace{20mu}{plasmid}\mspace{20mu}{DNA}\mspace{20mu}{supernatants}}}}{\mspace{34mu}{{{of}\mspace{20mu}{cells}\mspace{20mu}{incubated}\mspace{20mu}{with}}\mspace{20mu}{{control}\mspace{20mu}{plasmid}\mspace{20mu}{DNA}\mspace{20mu}{supernatants}}}} \times 100}$

As shown in Table 1, both human interferons displayed the characteristicpotent anti-proliferative activity against a wide variety of human tumorcell lines, with the most sensitive line being the NIH-OVCAR3 ovarianline and the least sensitive being the SK-OV-3 ovarian line. Also, thesupernatants from the mIFNα pDNA (VR4111)-transfected UM449 cellsinhibited the proliferation of murine B16F10 melanoma (generous giftfrom Dr. Suzuki at the University of Texas, Galveston, Tex.), murineCloudman melanoma S91 (American Type Culture Collection, Rockville,Md.), and murine glioma 261 cell lines (Division of Cancer TreatmentTumor Repository, National Cancer Institute, Frederick Cancer Researchand Development Center, Frederick, Md.) by 40, 42 and 17%, respectively.

TABLE 1 IFNω (VR4150) and IFNα (VR4102) in vitro biological assay:anti-proliferation activity against human tumor cell lines % reductionin cell proliferation (compared to control plasmid DNA supernatants)Cell line (tissue type) Interferon ω Interferon α NIH-OVCAR3 (ovarian)60 43 SCC-4 (squamous) 36 36 ACHN (renal) 41 35 A431 (epidermoid) 24 19SCC-15 (squamous) 29 29 U87MG (glioblastoma) 36 30 A375 (melanoma) 24 21PC3 (prostate) 20 22 UMUC3 (bladder) 14 6 A549 (lung) 17 15 MCF7(breast) 18 18 SK-OV-3 (ovarian) <10 <10

b. Antiviral Activity

An antiviral assay was performed to evaluate the ability of thesupernatants from the interferon plasmid DNA-transfected cells toprotect murine L929 cells or human A549 cells from infection by murineencephalomyocarditis (EMC) virus (Assay performed at IIT Institute,Chicago, Ill.). In vitro transfections were performed as described aboveand supernatants were collected from cells transfected with eitherVR4151 (hIFNω), VR4112 (hIFNα), VR4111 (mIFNα) or VR1055 (control).Antiviral activity of the supernatants was performed by IIT ResearchInstitute (Chicago, Ill.). The antiviral assay evaluated the degree ofprotection of either human A549 or murine L929 cells from infection withmurine encephalomyocarditis (EMC) virus. Briefly, 2.5×10⁴ L929 cellswere plated into 96-well plates and incubated for 24 h. Tissue culturesupernatants were serially diluted and added to the L929 cells whichwere incubated for another 24 h. Supernatants were then removed from thewells, the cells were washed and murine EMC virus was added to each wellat a multiplicity of infection of 0.04. Assay plates were incubatedfurther for 24 h followed by removal of supernatants, washing of wells,fixation with 5% formalin and staining with 1% crystal violet. Sampleswith interferon activity protected the cells from virus infection,resulting in darkly stained cell monolayers.

Supernatants from UM449 cells transfected with VR4151, VR4112, or VR4111had antiviral activity of 30,000, 3,000 or 30 Units/ml, respectively, onhuman A549 cells. When evaluated for antiviral activity on the murineL929 cell line, supernatants from UM449 cells transfected with VR4151,VR4112, or VR4111 had antiviral activity of 300, 1000 and 30,000Units/ml, respectively (Table 2) showing species specificity of thehIFNs for human cells and mIFNs for mouse cells.

TABLE 2 Antiviral Activity of interferon Plasmid DNA Interferon(Units/ml) Plasmid Human cell line Murine cell line VR4151 30,000 300VR4112 3,000 1,000 VR4111 30 30,000

Example 4 Systemic Interferon Therapy; Intramuscular Administration ofCytokine-Expressing Plasmids

Cell Lines and Tumor Models

Murine B16F10 cells were grown in RPMI-1640 (GibcoBRL) and 5% fetalbovine serum (FBS). Murine Cloudman S91 cells were grown in Ham's F-10medium with 25 mM Hepes, 0.1 mM, non-essential amino acids, 1 mM sodiumpyruvate, 0.05 mM β-mercaptoethanol, 2.5% FBS and 12.5% horse serum.Human melanoma UM449 cells were grown in RPMI-1640 with 10% FBS.

Murine glioma 261 tumor fragments and M5076 reticulum cell sarcoma cellswere obtained from the Division of Cancer Treatment Tumor Repository(National Cancer Institute, Frederick Cancer Research and DevelopmentCenter, Frederick, Md.). The glioma 261 tumor fragments (2 mm³) wereinitially implanted into the inguinal region of C57BL16 mice using a 13g trocar (Popper Sons, Inc., New Hyde Park, N.Y.). Tumors which grew inthe mice were used to establish a tumorigenic cell line. Minced tumorfragments were placed in Iscove's tissue culture medium with 10% FBS.Glioma 261 tumor cells began to attach to the flasks after several days,and the cells were propagated using standard tissue culture techniques.The M5076 cells were grown as ascites in C57BL/6 mice and frozen inliquid nitrogen. Human A431 cells were obtained from the American TypeCulture Collection and were grown in DMEM and 10% FBS.

C57BL/6, DBA/2, nude (nu/nu) and beige-nude (bg/nu/xid) female micebetween the ages of 6-8 weeks were obtained from Harlan Sprague Dawley(San Diego, Calif.). All animal experiments in this and the followingexamples were conducted in accordance with Vical's Institutional AnimalCare and Use Committee as well as the standards set forth in theNational Research Council guidelines concerning animal care and use.

To establish subcutaneous B16F10 melanoma tumors, C57BL/6, nude ornude-beige mice were injected subcutaneously on the flank with 104B16F10 cells. The Cloudman melanoma model was established bysubcutaneous injection of 10⁵ Cloudman S91 cells on the flank of DBA/2mice and the glioma 261 model was established by subcutaneous injectionof 5×10⁴ glioma 261 cells on the flank of C57BL/6 mice. To establishhuman epidermoid carcinomas, nude mice were injected subcutaneously onthe flank with 5×10³ A431 cells.

To establish intradermal M5076 tumors and liver metastases thereof,C57BL/6 mice were injected intradermally with 10⁵ M5076 reticulum cellsarcoma cells. In this model, primary intradermal tumors spontaneouslymetastasize to the liver. On day 29 after tumor cell injection, micewere sacrificed, livers removed and fixed in 10% buffered formalin(Fisher Scientific, Pittsburgh, Pa.), and the liver nodules werecounted.

To establish lung metastases of B16F10 melanoma, C57BL/6 mice wereinjected intravenously with 2×10⁴ B16F10 cells. On day 25 after tumorcell injection, the mice were sacrificed, lungs removed and fixed in 10%buffered formalin, and the lung nodules were counted.

To monitor the primary tumor growth, tumor sizes were determined 2-3times per week by measuring with calipers (l×w×h), and tumor volumeswere determined using the formula: tumor volume (mm³) 0.52 (l×w×h).

Tumor volume was analyzed using the Mann-Whitney U non-parametricStatistical Test to identify groups having significantly different meanweights. Mouse survival was analyzed using a Kaplan-Meier survival plotfollowed by a Logrank (Mantel-Cox) test to identify significantdifferences in survival between groups. Differences were consideredstatistically significant when the p value was less than or equal to0.05.

Intramuscular Injections

Fifty to 100 μg of plasmid DNA in 50 μl of saline was injected into therectus femoris muscle of each hind leg for a total DNA dose of 100 to200 μg. The muscle injections were performed using a 300 μl steriletuberculin syringe fitted with a 28G ½ needle (Becton Dickenson) and aplastic collar cut from a 200 μl micropipette tip. The collar length wasadjusted to limit the needle from penetrating further than 2 mm into therectus femoris muscle.

Serum Levels of Interferon Following Intramuscular Injection ofInterferon Plasmid DNA

Serum samples from C57BL/6 mice injected intramuscularly with eitherVR4111 (mIFNα plasmid) or VR1055 (control plasmid DNA) were analyzed ina mIFNα ELISA (n=0). For the ELISA, 96-well plates (Immulon 4HBX highbinding plates from Dynex Technologies, Chantilly, Va.) were coated withrat anti-mouse IFNα monoclonal antibody (mAb) from Caltag Laboratories(Burlingame, Calif.) at a concentration of 5 μg/ml in 100 mM sodiumcarbonate buffer, pH 9.5 (50 μl per well). Plates were incubated withthe coating mAb for 16 hours at 4° C. The plates were then washed 3times with a wash buffer (phosphate-buffered saline (PBS)), pH 7.2 and0.05% Tween-20 (Sigma, St. Louis, Mo.)). The plates were blocked in PBScontaining 3% bovine serum albumin (BSA, Sigma) and 0.05% Tween-20 (400μl per well) and incubated for 24 hours at 4EC followed by washing threetimes with wash buffer.

Serum samples (10 μl) from mice injected intramuscularly with VR4111(mIFNα) were mixed with 40 μl of assay buffer (PBS, 1% BSA, 0.05%Tween-20) and the mixture was added to each assay well. The positivecontrol was mIFNα polypeptide (Biosource International, Camarillo. CA),which was serially diluted in assay buffer and 50 μl was added to thepositive control wells. The negative control was serum from miceinjected intramuscularly with VR1055. After adding the test samples andcontrols, the plates were incubated for 16 hours at 4° C. The plateswere then washed 6 times with wash buffer, followed by addition of asheep anti-mouse IFNα polyclonal antibody (pAb) (BiosourceInternational, Camarillo, Calif.). The PAb was added at a 1:500 dilutionin assay buffer (50 μl per well) and the plates were incubated for 5hours at room temperature.

Following incubation with the pAb, the plates were washed six times withwash buffer followed by addition of anti-sheep IgG conjugated withperoxidase (Sigma) at a 1:5000 dilution in assay buffer (50 μl per well)and incubated for 1 hour at room temperature. The plates were washed 6times with wash buffer and 200 μl of 3,3′,5,5′-tetramethylbenzidineliquid substrate (TMB) (Sigma Chemical Co.) was added per well. Plateswere incubated at room temperature for 30 minutes, followed bydetermination of the optical density of the wells at 650 nm. A standardcurve was generated by plotting the ng/ml of mIFNα polypeptide versusthe optical density at 650 nm. The concentration of mIFNα in the testserum samples was determined from the linear portion of the mIFNαstandard curve. The sensitivity of the mIFNα ELISA was 50 ng/ml.

C57BL/6 mice injected intramuscularly with VR4111 had detectable serumlevels of mIFNα after 5 intramuscular injections of 100 μg VR4111 (twicea week for two weeks, followed by one injection the next week). Theaverage serum level of mIFNα after 5 intramuscular injections of VR4111was 1465 ng/ml (average of 16 mice). At the time of this study, nocommercial mIFNα ELISA kit had been developed. Since sensitivity of thein-house mIFNα ELISA is 50 ng/ml, lower serum levels of mIFNα couldexist in the mice at earlier timepoints, but we were unable to detectthis in our ELISA.

To determine the serum levels of hIFNα, C57BL/6 or nude mice received asingle intramuscular injection of 100 μg of VR4151 (hIFNω plasmid DNA)or VR1055 (control plasmid DNA) (50 μg per leg bilaterally) in therectus femoris. Serum samples were collected daily over a two weekperiod and analyzed in the hIFNω ELISA kit (Alexis, San Diego, Calif.)which was sensitive to 2 pg/ml. Serum samples were collected from 4-5mice per day. In the C57BL/6 mice, measurable serum levels of hIFNα weredetected as early as one day after injection (69 pg/ml) (FIG. 2A). Inthese mice, peak serum levels were found six days after injection (254pg/ml) and expression continued out to day 14 (50 pg/ml), the finaltimepoint of the study.

In nude mice, serum levels of IFNω were found as early as one day afterinjection (133 pg/ml). Peak serum levels were found on day 7 (648 pg/ml)and expression continued out to day 14 (134 pg/ml), the final time pointof the study (FIG. 2B). Thus, interferon could be detected in the serumafter a single intramuscular injection of an interferon-encoding plasmidDNA.

Systemic Interferon Treatment Inhibits Primary Tumor Growth

As shown in FIGS. 3-5 and FIG. 7A, mice bearing different tumors werefound to significantly benefit from intramuscular injection of differentcytokines. To test the efficacy of IFNα plasmid, C57BL/6 mice bearingsubcutaneous B16F10 melanoma, subcutaneous glioma 261, or intradermalM5076 tumors, or DBA/2 mice bearing subcutaneous Cloudman melanoma wereinjected with 100 μg either of VR4111 (mIFNα) or VR1055 (control), twiceper week for three weeks, beginning on day 4 after tumor cell injection(n=8-10 mice per group). In all three subcutaneous tumor models, themice treated intramuscularly with VR4111 had a significant reduction intumor volume (p<0.05) (FIGS. 3A, 3C, and 3E), and a significantenhancement of survival (p<0.02) compared to the mice that received thecontrol plasmid (FIGS. 3B, 3D, and 3F). In the intradermal tumor model,mice treated with intramuscular VR4111 had a significant reduction inprimary tumor volume (p<0.001) compared to the mice that received thecontrol plasmid (FIG. 7A).

To compare the efficacy of IL-2, IL-12 to IFNα plasmids, C57BL/6 micebearing subcutaneous B16F10 melanoma were injected with 100 μg of VR4111(mIFNα), VR4001 (mIL-12), VR1110 (mIL-2), or VR1012 (control) (n=15-16mice per group) twice per week for three weeks. Mice receivingintramuscular injections of VR4111 had a significant reduction in tumorgrowth (p<0.0002) (FIG. 4A) by day 17 as well as a significant increasein survival (p=0.00001) (FIG. 4B). By day 28 of the study, 100% of theVR4111-treated mice were still alive, compared to only 20% of theVR1012-treated mice. Mice treated with VR1110 had a modest reduction intumor growth by day 17 (p<0.02) (FIG. 4A) but did not have an increasein survival compared to the VR1012-treated mice (FIG. 4B). Mice treatedwith VR4001 also had a modest reduction in tumor growth by day 17(p<0.03) (FIG. 4A) as well as a significant increase in survival(p=0.02) (FIG. 4B). By day 28, 55% of the mice treated with VR4001 werealive, compared to 20% of the VR1012-treated mice.

To test the efficacy of IFNω, mice bearing human A431 tumors between30-80 mm³ were injected intramuscularly with 200 μg of either VR4151(hIFNω) or VR1055 (control) twice per week for three weeks (n=15). Micebearing subcutaneous A431 tumors and injected intramuscularly withVR4151 had a significant reduction in tumor volume (p<0.05) (FIG. 5A)and a significant increase in survival (p<0.05), compared to the micethat received the control plasmid (FIG. 5B).

Systemic mIFNα Plasmid DNA Treatment Inhibits the Growth of TumorMetastases

As shown in FIG. 6 and FIG. 7, mice bearing different tumor metastaseswere found to significantly benefit from intramuscular injection ofIFNα. C57BL/6 mice bearing lung metastases of B16F10 melanoma wereinjected intramuscularly with 100 μg of either VR4111 (mIFNα) or VR1055(control) twice per week for three weeks, beginning on day 4 after tumorcell injection (n=10). On day 25 after tumor cell injection, the micewere sacrificed, lungs removed and fixed in 10% buffered formalin(Fisher Scientific, Pittsburgh. PA) followed by counting of lungnodules.

While 70% of the control plasmid-treated mice had lung nodules that weretoo numerous to count, 80% of the mice treated with mIFNα plasmid DNAhad 10 or fewer nodules (FIG. 6). TNTC denotes lungs with nodules thatwere too numerous to count.

In the liver metastases model, C57BL/6 mice bearing intradermal M5076murine reticulum sarcoma were injected intramuscularly with 100 μg ofeither VR4111 or VR1055 twice per week for three weeks, beginning on day4 after tumor cell injection (n=10-13 mice per group). On day 29 aftertumor cell injection, the mice were sacrificed, livers removed and fixedin 10% buffered formalin (Fisher Scientific, Pittsburgh, Pa.) followedby counting of liver nodules.

While the control plasmid-treated mice had a mean of 190 hepatic tumornodules or had nodules that were too numerous to count, mIFNα plasmidDNA-treated mice had a mean of 35 hepatic tumor nodules (FIG. 7B).

These results demonstrate that intramuscular injection of mIFNα plasmidDNA can effectively inhibit the growth of both primary and metastaticlesions. Thus, for patients with metastatic disease, intramuscularadministration of therapeutic plasmid DNAs would be advantageous for thetreatment of undiagnosed or inaccessible metastatic lesions.

Regimen Optimization of mIFNα Therapy in the B16F10 Melanoma Model

A regimen optimization study was conducted to evaluate the antitumorefficacy of fewer injections and/or a lower dose of VR4111 (mIFNα) inthe subcutaneous B16F10 melanoma model. C57BL/6 mice were injected witheither 100 or 50 μg of VR4111 or VR1055 over a 6 week period (n=10).Mice received intramuscular injections either twice per week, once perweek or once every other week. All intramuscular injections began fourdays after the initial subcutaneous B16F10 tumor cell injection. Micewhich received intramuscular injections of 100 μg of VR4111 at any ofthe time courses had a significant reduction in tumor volume (p<0.005)and a significant increase in survival (p=0.007) (FIGS. 8A and 8B). Themice which received the 100 μg dose of VR4111 once every other week for6 weeks had a total of only three intramuscular injections withsignificant antitumor efficacy. In contrast, mice receiving the 50 μgdose of VR4111 revealed a dose response based on the frequency ofinjection. While mice injected with 50 μg of VR4111 once or twice perweek had a significant reduction in tumor volume (p≦0.03), and asignificant increase in survival (p=0.002), mice injected only onceevery other week did not have a significant antitumor response foreither tumor growth or survival (FIGS. 8C and 8D).

Mechanism of mIFNα Antitumor Effect

To investigate the role of natural killer (NK) and T cells in mediatingthe antitumor effect of systemically delivered mIFNα, VR4111 or VR1055was administered intramuscularly to nude mice (which are T celldeficient) and to beige-nude mice (which are NK and T cell deficient)bearing subcutaneous B16F10 melanoma tumors. Beginning on day 4 afterinjection of 10⁴ B16F10 cells, 50 μg of plasmid DNA in 50 μl of salinewas injected into the rectus femoris muscle of each hind leg for a totalDNA dose of 100 μg twice per week for three weeks (n=15 mice per group).

There was neither a significant reduction in tumor volume norenhancement of survival in the nude mice (FIGS. 9A and 9B) or beige-nudemice (FIGS. 9C and 9D). These results suggest that T cells may berequired for the mIFNα antitumor response. NK cells appeared not to berequired for the antitumor effect since nude mice (NK⁺) did not have agreater antitumor response compared to the beige-nude mice (NK⁻).

To further explore the role of T cells in the antitumor effect of mIFNαDNA therapy, C57BL/6 mice bearing subcutaneous B16F10 tumors wereinjected with depleting doses of monoclonal antibodies (mAbs) specificfor either CD4⁺ or CD8⁺ T cells. For depletion of T cell subsets,anti-CD4 (clone GK1.5, rat IgG) and anti-CD8 (clone 2.43, rat IgG)hybridomas (American Type Culture Collection, Rockville, Md.) were usedto generate the corresponding mAb. The anti-CD8 hybridoma was grown asascites in nude mice and the mAbs were purified from ascites using ionexchange chromatography (Harlan Bioproducts for Science, San Diego,Calif.). The anti-CD4 hybridoma was grown in vitro with Dulbecco'sModified Eagle Medium, 10% fetal bovine serum and low IgG. The anti-CD4mAb was purified from tissue culture supernatant by ammonium sulfateprecipitation to 30%. The protein pellet was resolubilized andextensively dialyzed in Dulbecco's Ca²⁺/Mg²⁺-free phosphate-bufferedsaline (Zymed Laboratories Inc., San Francisco, Calif.).

Beginning on day 4 after subcutaneous injection with 104 B16F10 cells,mice were injected intramuscularly with 100 μg of either VR4 μl orVR1055 twice per week for three weeks. For depletion of CD4⁺ and CD8⁺ Tcells, mice were injected intraperitoneally with 500 μg of either theanti-CD4 mAb (clone GK1.5, rat IgG) or anti-CD8 mAb (clone 2,43, ratIgG) one day prior to each intramuscular DNA injection (n=10 mice pergroup). Control tumor-bearing mice were injected intraperitoneally with500 μg of normal rat IgG (Sigma Chemical Co., St. Louis, Mo.) (n=10). Toassure complete depletion, sentinel mice were injected according to thesame regimen, and once per week, spleens were collected, dissociated andassessed for the presence of CD4⁺ and CD8⁺ T cells. Spleen cells werestained with FITC-conjugated anti-CD4 and PE-conjugated anti-CD8 mAbs(Pharmingen, San Diego, Calif.) and analyzed by flow cytometry(Cytometry Research Services, San Diego, Calif.). The depletion of CD4⁺and CD8⁺ T cells was consistently greater than 98%, as determined bycytometry.

The mIFNα DNA therapy significantly reduced tumor growth (p≦0.002) andenhanced survival (p≦0.008) of both normal mice and mice depleted ofCD4⁺ T cells, compared to mice injected with control plasmid and treatedwith normal IgG (FIGS. 10A and 10B). These results suggest that CD4⁺ Tcells are not required for the mIFNα antitumor effect. In contrast, micedepleted of CD8⁺ T cells and injected with mIFNα DNA displayed tumorvolumes and survival profiles that were not significantly different frommice treated with the control plasmid (FIGS. 10A and 10B). This resultsuggests that CD8⁺ cells are involved in the mIFNα antitumor response.

Example 5 Local Interferon Therapy: Intratumoral Administration ofInterferon Plasmids

The anti-tumor activity of IFNω and IFNα was evaluated in vivo in nudemice bearing subcutaneous human ovarian (NIH-OVCAR3) or human melanoma(A375) (nude/human/xenograft model), or in C57BL/6 mice bearing murinemelanoma (B16F10) tumors following intratumoral administration of DNAcomplexed with a cationic lipid.

Cell Lines and Tumor Models

Athymic nude (nu/nu) and C57/BL/6 mice between the ages of 6-10 weekswere obtained from Harlan Sprague Dawley (San Diego, Calif.).

Human A375 melanoma cells and human NIH-OVCAR3 ovarian carcinoma cellswere obtained from the American Type Culture Collection (Rockville,Md.), and grown in Dulbecco's modified Eagle's medium (GibcoBRL,Gaithersburg, Md.) supplemented with 10% FBS. B16F10 cells were agenerous gift from Dr. Suzuki at the University of Texas (Galveston,Tex.). Cells were grown in RPMI-1640 (GibcoBRL) and 5% fetal bovineserum (FBS).

To establish subcutaneous A375 melanoma tumors and subcutaneousNIH-OVCAR3 ovarian tumors, athymic nude/nude mice (10 mice/group) wereinjected subcutaneously with 5×10⁶ A375 cells and 5×10⁷ NIH-OVCAR3 cellsrespectively. To establish subcutaneous murine B16F10 melanoma tumors,C57BL/6 mice were injected subcutaneously with 10⁴ B16F10 cells.

Mice were monitored for tumor growth and survival. Tumor sizes weredetermined 3 times per week by measuring with calipers (l×w×h) and tumorvolumes were determined using the formula: tumor volume (mm³)=0.52(l×w×h). Statistical analysis was done as described in Example 4.

Local Interferon Plasmid DNA Inhibits Tumor Growth

Established subcutaneous A375 human melanoma and NIH-OVCAR3 humanovarian carcinoma tumors in nude mice were transfected in vivo byintratumoral administration of pDNA/DMRIE/DOPE (DNA:lipid) complexes(n=10). When tumors became palpable (80-300 mm³, at day 27 post tumorcell implant for the A375 cells, and at day 41 post tumor cell implantfor the NIH-OVCAR3 cells), mice were injected intratumorally with 100 μgof VR4112 (hIFNα), VR4151 (hIFNω), VR1055 (control) or VR1012 (control)complexed with DMRIE/DOPE (1:1 DNA:DMRIE mass ratio). Tumor bearinganimals were treated intratumorally with DNA:lipid for 6 consecutivedays followed by 5 treatments every other day for a total of 11treatments (A375 melanoma model), or every other day for a total of 11treatments (NIH-OVCAR3 ovarian cancer model).

As shown in FIG. 11A, in the A375 model of melanoma, the directintratumoral injection of VR4151:lipid complex for 6 consecutive days,followed by 5 additional injections every other day (100 μg plasmidDNA/injection, total of 11 injections), resulted in a statisticallysignificant slowing of tumor growth, as compared to the control (p<0.03,days 40-44).

As shown in FIG. 2B, in the NIH-OVCAR3 model of ovarian cancer, thedirect intratumoral injection of VR4151:lipid complex every other dayfor a total of 11 injections (100 μg plasmid DNA/injection), resulted insustained and statistically significant reduction in tumor growth ascompared to the control plasmid control (p<0.001-0.05, Days 45-65). Asimilar treatment regimen with VR4112:lipid was found to have a moderateeffect on tumor growth which only reached statistical significance vs.the control plasmid at two time-points during the study (p<0.05, days 53and 57).

As shown in FIG. 12A, in the B16F10 melanoma model, direct intratumoralinjection of mIFNα resulted in decrease in tumor volume. Once palpabletumors were established (80-300 mm³) on day 12 after tumor cellinjection in C57BL/6 mice bearing subcutaneous B16F10 melanoma tumors,mice were injected intratumorally with 100 μg of either VR4101 (mIFNα)or VR1012 (control) complexed with the cationic lipid, DMRIE/DOPE at aDNA/DMRIE mass ratio of 1:1 in a 100 μl volume. Mice received sixconsecutive intratumoral injections of either VR4101 or VR1012 (n=10mice per group). As shown in FIG. 12A, although not statisticallysignificant, intratumoral injection of VR4101 resulted in a 54%reduction in tumor volume by day 19 of the study. As shown in FIG. 12B,a significant increase in survival (p=0.02) was found for theVR4101-treated mice, compared to the mice that received VR1012.

Example 6 Local Cytokine Therapy: Intraperitoneal Administration ofCytokine-Expressing Plasmids

The goal of this example is to show that the present invention providesan effective method of treating malignant tumors of murine ovariancarcinoma via intraperitoneal (i.p.) injection of cytokine-expressingplasmid DNA. Since late-stage ovarian carcinoma is usually limited tothe peritoneal cavity, it was envisioned that continuous secretion of acytokine in this cavity would produce beneficial anti-tumor immuneresponse. In particular, the present example clearly shows that theovarian cancer therapy by intraperitoneal injection of acytokine-expressing plasmid DNA:lipid complexes (1) results in sustainedlevels of the cytokine in the ascites, avoiding the need for frequentinjections of the protein (in contrast to intraperitoneal injection ofrecombinant cytokine wherein the cytokine level declines shortly afterinjection), (2) targets tumor ascites, rather than peritoneal tissues(suggesting that systemic cytokine side effects should be reduced usingthis method), (3) inhibits tumor growth and enhances survival, and (4)can be combined with debulking of tumor ascites to enhance the antitumoreffect.

Cell Lines and Tumor Models

As a model for human ovarian cancer, the murine ovarian teratocarcinoma(MOT) model in C3H/HeN mice was used. MOT exhibits many of thecharacteristics of late-stage human ovarian cancer including peritonealspread, production of tumor ascites and tumor cell blockage oflymphatics (Ozols et al., 1979 and Fekete et al., 1952).

Murine ovarian teratocarcinoma (MOT) cells were obtained from Dr. RobertKnapp and Dr. Robert C. Bast at the Dana-Farber Cancer Center (Boston,Mass.). The MOT cells (105) were grown by serial intraperitoneal (i.p)transplantation in C3H/HeN mice and a stock of the cells was frozen inliquid nitrogen.

CTLL-2 cells were obtained from the American Type Culture Collection(ATCC. Rockville, Md.) and were grown in RPMI-1640 with glutamine, 1%sodium pyruvate, 1% penicillin-streptomycin (Life Technologies,Gaithersburg, Md.), 10% fetal bovine serum (HyClone, Logan, Utah) and 10U/ml murine IL-2 (Boehringer Mannheim, Indianapolis, Ind.).

C3H/HeN and nude (nu/nu) female mice between the ages of 6-10 weeks wereobtained from Harlan Sprague Dawley (San Diego, Calif.). All animalexperiments were conducted in accordance with Vical's InstitutionalAnimal Care and Use Committee as well as the standards set forth in theNational Research Council guidelines concerning animal care and use.

To establish i.p. MOT tumors, C3H/HeN mice were injected i.p. with 10⁵MOT cells in 100 ul of medium. In the MOT tumor model, tumor growth istypically monitored by weighing the mice which reflects the increase involume of tumor ascites (Berek et al., Cancer Res., 44:1871-1875, 1984).The nude mouse study were performed in the same manner as the studies inC3H/HeN mice with injection i.p. of 105 MOT cells and monitoring theweight of the mice. Statistical analysis on mouse weight and survivalwas done as described in Example 4.

Preparation of Plasmid DNA:Lipid Complexes and Intraperitoneal Injection

To yield a pDNA:DMRIE mass ratio of 1:1, 100 μg of VR1110 (mIL-2) wasdiluted in 500 ul 0.9% saline (Radix Labs, Eau Claire, Wis.), DMRIE/DOPElipid (100 μg DMRIE) was diluted in 500 ul of 0.9% saline in a separatevial, and the pDNA and cationic lipid were combined and vortexed for 5seconds. To yield a pDNA:DMRIE mass ratio of 5:1, 500 μg of mIL-2 pDNAwas diluted in 500 ul 0.9% saline (Radix Labs, Eau Claire, Wis.),DMRIE/DOPE lipid (100 μg DMRIE) was diluted in 500 ul of 0.9% saline ina separate vial, and the pDNA and cationic lipid were combined andvortexed for 5 seconds.

The 1 ml pDNA:DMRIE/DOPE (DNA:lipid) complex was injected i.p. into micebearing i.p. MOT tumors on various days after tumor cell implant.Control MOT tumor-bearing mice received i.p. injections of VR1012(control):lipid at the same ratio (1:1 pDNA:DMRIE, 100 μg pDNA) and wereinjected i.p. on the same days as the cytokine-expressing or reportergene treatment groups.

Intraperitoneal Injection of Plasmid DNA:Lipid Results in TargetedExpression in Tumor Ascites

The pDNA:lipid therapy was evaluated for the ability to target malignantcells within a cavity. C3H/HeN mice were injected i.p. with 105 MOTcells followed by i.p. injection of 100 μg of VR1223 (luciferase):lipid(1:1 pDNA:DMRIE mass ratio) on days 5 and 6 after tumor cell implant.Control MOT tumor-bearing mice were injected i.p. with 100 μg of eitherVR1012:lipid or VR1223 without lipid on days 5 and 6 after MOT tumorcell injection. An additional group of control mice did not receive MOTtumor cells and were injected i.p. with VR1223:lipid on the same days asthe other treatment groups (n=3). Three days later the mice wereeuthanized and tumor ascites and tissues (liver, kidney, spleen,diaphragm, intestine and ovary) were collected. Luciferase was extractedfrom the tissues by freeze-thawing and grinding of the samples in celllysis reagent (Promega, Madison, Wis.) as previously described (Hartikkaet al., Hum. Gene Ther., 7:1205-1217, 1996). The tumor ascites wasdiluted 1:5 in cell lysis reagent followed by three cycles offreeze-thaw and collection of supernatant from the cell lysate. Sampleswere read in a microplate luminometer (Dynatech, Chantilly, Va.)following addition of luciferase substrate (Promega, Madison, Wis.). Therelative light units (RLU) of the samples were determined from astandard curve using purified firefly luciferase (AnalyticalLuminescence Laboratory, Sparks, Md.). The protein concentration of eachsample was determined using the BCA protein assay kit (Pierce ChemicalCompany, Rockford, Ill.). Luciferase levels were expressed as RLU per mgof protein. There may be a decrease in IL-2 pDNA expression from day 1to day 3 post DNA injection.

On day three, tumor ascites had 900,000 RLU of luciferase/mg, whilediaphragm and ovary tissue had only 327 and 16 RLU/mg (FIG. 13). Kidney,liver, spleen and intestinal tissue had no detectable luciferaseactivity. These results suggest that i.p. injection of pDNA:lipidcomplexes appears to target the tumor ascites in the peritoneal cavitywith limited or negligible transfection of surrounding tissues.Luciferase detected in the diaphragm and ovary tissue was only found inMOT tumor-bearing mice injected with VR1223:lipid. When naive non-tumorbearing mice were injected with the same DNA:lipid complex, noluciferase activity was found in anyof the tissues (data not shown).These results suggest that the low levels of luciferase in the diaphragmand ovary in MOT tumor-bearing mice may reflect metastases of tumorcells to these tissues. Tumor-bearing mice injected with luciferase pDNAwithout cationic lipid had no luciferase activity in either tumorascites or surrounding tissues, indicating that lipid is required foroptimal in vivo transfection of ovarian tumor ascites. Mice injectedwith VR1012:lipid had no detectable luciferase activity in either tumorascites or tissues.

A follow-up study investigated the specific cell type in the ovariantumor ascites that was transfected after i.p. injection of a reportergene pDNA:DMRIE/DOPE complex. On days 5 and 6 after tumor cell implant(10⁵ cells), C3H/HeN mice were injected i.p. with 100 μg of VR1412(β-galactosidase (β-gal)):lipid, VR1012:lipid (1:1 DNA:DMRIE massratio), or with VR1412 without cationic lipid (n=3 mice per group). Oneday later the mice were sacrificed and the tumor ascites was collected.The ascites was spun at 2500 rpm for 2 minutes to pellet the cells, andthe supernatant was removed. The tumor cells were fixed in 10% bufferedformalin (Fisher Scientific, Pittsburgh, Pa.), placed in a cryomoldcontaining OCT embedding medium (VWR, S. Plainfield, N.J.), frozen inisopentane and then stored at −70° C. The embedded and frozen sampleswere then cryostat sectioned (5 um), further fixed (0.5% glutaraldehydein PBS), washed (PBS), stained with X-gal reagent (1 mg/ml X-gal dilutedin PBS containing 5 mM potassium ferricyanide, 5 mM potassiumferrocyanide, and 1 mM magnesium chloride), washed again (PBS), andcounterstained with hematoxylin and eosin. (The samples were cryostatsectioned and stained by Pathology Associates (Frederick, Md.).)

The ascites from mice treated with either VR1012 or VR1412 without lipidhad no β-gal activity in the samples. In contrast, the tumor ascitesfrom mice injected with VR1412:lipid had 5-gal staining primarily in thetumor cells (data not shown). In a few slides, several macrophages andlymphocytes were also positive for β-gal while neutrophils were negativefor β-gal.

Intraperitoneal Injection of IL-2 pDNA:lipid Results in SustainedExpression of IL-2 in Tumor Ascites

A time-course study was done to determine the length of time that IL-2could be detected after multiple i.p. injections of IL-2 pDNA:lipid or asingle i.p. injection of either IL-2 protein or IL-2 pDNA:lipid in micebearing i.p. ovarian tumor ascites. Beginning on day 5 after tumor cellinjection, mice were injected multiple times with VR1110 (mIL-2):lipidor a single time with VR1110:lipid or IL-2 protein. Mice were sacrificedat various times and ascites and serum were analyzed for IL-2 levels.Ascites was collected from the sacrificed mice, the samples were spun at14,000 rpm for 2 minutes and the supernatant was harvested. Blood wascollected from the mice on the same day as the ascites collection andthe serum was separated from blood cells by allowing the blood to clotin serum separator tubes (Microtainer, Becton Dickinson, Franklin Lakes,N.J.) followed by centrifugation at 14,000 rpm for 10 minutes andcollection of the serum supernatant. IL-2 concentration (pg/ml) in theascites and serum samples was determined using a murine IL-2 ELISA (R &D Systems, Minneapolis, Minn.). Since the volume of tumor ascitesincreases over time, the volume of ascites was also determined for eachmouse. The total concentration of IL-2 in ascites was determined usingthe formula: IL-2 pg/ml×ml of ascites=pg IL-2/total ascites. Serum IL-2concentrations were reported as pg/ml.

IL-2 in Serum and Ascites after Multiple Injections of IL-2 pDNA: Lipid.

Beginning on day 5 after tumor cell injection, mice were injected withVR1110:lipid for either 2, 4 or 6 consecutive days or with controlVR0112:lipid for 6 consecutive days (100 μl of plasmid DNA complexedwith 100 μl DMRIE/DOPE at 1:1 mass ratio in a total volume of 1 ml). Anadditional group of mice received VR1110 that was not complexed withDMRIE/DOPE. Every two days for up to 17 days after the DNA:lipidinjections, 3-4 mice were sacrificed per treatment group and ascites andserum were collected and analyzed using mIL-2 ELISA assay as describedabove.

Two injections of VR1110:lipid (100 μl DNA per day 1:1 DNA:cationiclipid mass ratio) into mice bearing i.p. MOT ovarian tumors yielded highlevels of IL-2 protein in the tumor ascites. One day after VR1110:lipidi.p. injection, 28,000 pg/ml of IL-2 was measured in the tumor ascites(Table 3). IL-2 expression in the ascites continued for over two weeksafter DNA:lipid injection with 750 pg/ml detected 17 days after the lastpDNA:lipid injection. Mice injected with either four or six consecutiveinjections of VR1110:lipid also had high levels of IL-2 in the tumorascites; however, due to the very high expression levels after morefrequent VR1110:lipid injections, IL-2-mediated side effects were notedin the mice which did not survive beyond day 9 or 13 after DNAinjection. In contrast, two consecutive injections of VR1110 plusDMRIE/DOPE did not cause observable IL-2 side effects yet IL-2expression levels remained high for over 2 weeks. The IL-2 expressedafter i.p. DNA:lipid injection of MOT-bearing mice appeared to remainlocalized in the peritoneal cavity as the IL-2 serum levels afterVR1110:lipid i.p. injection were always less than 10% of the levels inthe tumor ascites. Injection of VR1110 without lipid yielded very lowlevels of IL-2 in ascites and serum (0-32 pg/ml). Injection of thecontrol vector, VR1012, resulted in only background levels of IL-2.

TABLE 3 Days post tumor cell injection Treatment 7 9 11 13 15 17 19 2123 mIL-2 concentration in ascites (pg/ml) VR1110 (mIL-2) 28 12 0 1 0 1 0without DM/DP, 6 injs. VR1012 (control) + 0 0 8 0 0 1 43 DM/DP, 6 injs.VR1110 (mIL-2) + 7196 7716 7824 3895 3200 DM/DP, 6 injs. VR1110(mIL-2) + 3524 4187 5968 3050 3984 2392 441 DM/DP, 4 injs. VR1110(mIL-2) + 28882 4750 11725 8047 1246 1445 1407 774 753 DM/DP, 2 injs.mIL-2 concentration in serum (pg/ml) VR1110 (mIL-2) 0 4 0 32 0 0 0without DM/DP, 6 injs. VR1012 (control) + 0 0 0 0 0 0 62 DM/DP, 6 injs.VR1110 (mIL-2) + 66 85 34 5 4 DM/DP, 6 injs. VR1110 (mIL-2) + 114 81 4010 3 2 0 DM/DP, 4 injs. VR1110 (mIL-2) + 625 418 181 76 6 0 1 0 0 DM/DP,2 injs.

IL-2 in Serum and Ascites After Single Injection of pDNA:lipid InjectionCompared to Protein Injection.

Five days after i.p. injection of 10⁵ MOT tumor cells, C3H/HeN mice wereinjected with 100 μg of either VR1110:lipid or VR1012:lipid (1:1DNA:DMRIE mass ratio) or with 100 μg of VR1110 without lipid. For theIL-2 protein-treated group, mice were injected with 1 μg recombinantmurine IL-2 protein (R & D Systems, Minneapolis, Minn.). The pDNA:lipid,pDNA alone, or recombinant protein was injected i.p. in a total volumeof 1 ml saline per mouse. Five mice from each group were sacrificedbeginning at 4 hours and continuing on days 1, 2, 3, 6 and 10 post DNAor protein injection. Ascites and serum were collected and analyzedusing mIL-2 ELISA assay as described above.

Mice injected i.p. with IL-2 protein had peak levels of IL-2 in ascites(10 ng) at 4 hours after injection of IL-2 and a 1000-fold reduction inIL-2 one day later (0.009 ng) (FIG. 14A). In contrast, mice injectedwith IL-2 pDNA: lipid had peak IL-2 levels in ascites 2 days afterinjection (64 ng) and only a 2.6 fold reduction in IL-2 by 10 days afterinjection (25 ng) (FIG. 14A). These results indicate that mice receivingIL-2 pDNA:lipid have more sustained levels of IL-2 in the ascitescompared to mice receiving IL-2 protein. Tumor-bearing mice injectedi.p. with either VR1012:lipid or VR1110 without cationic lipid had noIL-2 in the tumor ascites. In a related study, MOT tumor-bearing miceinjected i.p. with 10-fold less VR1110:lipid (10 μg DNA) still haddetectable IL-2 in the tumor ascites 11 days after the VR1110:lipidinjection (data not shown).

Serum levels of IL-2 after either i.p. protein or DNA injectionreflected a similar pattern as that found in tumor ascites; however, theserum IL-2 levels were markedly reduced compared to the ascites IL-2levels. Four hours after protein injection, IL-2 in the serum was 2.4ng/ml and negligible by one day after protein injection. Serum levels ofIL-2 one day after VR1110:lipid injection was 1 ng/ml and undetectableby 6 days after the injection (FIG. 14B). These results suggest that themajority of the IL-2 after either IL-2 protein or pDNA:lipid deliveryremains in the peritoneal cavity.

Intraperitoneal Injection of IL-2 Plasmid DNA:lipid Inhibits TumorGrowth and Enhances Survival

Six consecutive-day treatments. The plasmid DNA:lipid therapy wasevaluated for the ability to reduce tumor growth and to increasesurvival of mice with MOT tumors. On day 5 after MOT tumor cellinjection, mice were injected i.p. with 100 μg of either VR1110 orVR1012, both complexed with DMRIE/DOPE. The plasmid DNA was complexed ateither a 5:1 or 1:1 DNA:DMRIE mass ratio. An additional treatment groupreceived VR1110 that was not complexed with lipid. A total volume of 1ml DNA:lipid or DNA alone in physiological saline was injected i.p. TheDNA treatments occurred over 6 consecutive days, beginning on day 5(days 5-10). MOT tumor growth was measured by weighing the mice. Alltreatment groups consisted of 10 mice per group.

The high IL-2 expression level in ascites was accompanied by significantantitumor effects. Mice treated with VR1110:lipid on days 5-10 aftertumor cell injection had a significant reduction in MOT tumor growthcompared to the mice treated with the VR1012:lipid (p=0.01) (FIG. 15A).A significant enhancement in survival was also found for mice injectedi.p. with VR1110:lipid (p=0.05) (FIG. 15B).

Complexing the pDNA with a cationic lipid seemed necessary for theantitumor effect as treatment of tumor-bearing mice with VR1110 withoutlipid was not effective (FIGS. 15E and 15F). Furthermore, a 1:1DNA:cationic lipid mass ratio was found to be more effective at reducingtumor burden and increasing survival than a 5:1 DNA:cationic lipid massratio (FIGS. 15C and 15D).

Three alternative-day treatments. C3H/HeN mice bearing i.p. MOT tumorascites were injected i.p. with VR1110:lipid or with VR1012:lipid (100μg DNA) on days 5, 8 and 11 after tumor cell implant. By day 14 posttumor cell injection, mice treated with VR1110:lipid had a significantreduction in mean weight (p=0.001) compared to the mice treated with thecontrol pDNA:lipid (FIG. 16A). In addition, a significant increase insurvival (p=0.008) was found for the VR1110:lipid-treated mice comparedto the mice treated with the VR1012:lipid (FIG. 16B). By day 26 posttumor cell injection, none of the mice treated with the VR1012 werestill alive, while 50% of the mice treated with VR1110:lipid remainedalive. By day 55 post tumor cell injection, 20% of the mice treated withVR1110:lipid appeared to be tumor-free.

Whether the IL-2 pDNA:lipid antitumor effect required T cells wasinvestigated by implanting nude mice with i.p. MOT tumors followed bysame VR1110:lipid regimen used in the C3H/HeN tumor-bearing mice (DNAtreatment on days 5, 8 and 11 after tumor cell implant). No significantantitumor effect was found for the nude mice treated with VR1110:lipidsuggesting that T cells may be required for the antitumor effect (datanot shown).

IL-2 Plasmid DNA:lipid Antitumor Effect Enhanced by Debulking of TumorAscites

Debulking of tumor ascites is commonly performed on human ovarian cancerpatients. A similar procedure was performed in the mice bearing MOTtumors and treated with VR1110:lipid. Mice bearing MOT tumors andinjected i.p. with 100 ul DNA:lipid on days 5-10 as described above (1:1DNA:lipid mass ratio), were also debulked of tumor ascites on day 14after tumor cell injection (4 days after the last DNA:lipid injection).Mice were debulked of 5 ml of tumor ascites by insertion of a 22 Gneedle attached to a 5 ml syringe and removal of 5 ml of fluid. The micewere anesthetized with methoxyflurane during the debulking procedure.All treatment groups in this experiment consisted of 8-10 mice pergroup.

Debulking of ovarian tumor ascites in mice previously treated with IL-2plasmid DNA:lipid further enhanced the efficacy of the treatmentresulting in a significant reduction in tumor growth (p=0.01) and anincrease in survival. Forty four percent of the IL-2 plasmidDNA:lipid-treated and debulked mice were alive on day 57 vs. 17% of theplasmid control-treated and debulked mice (FIG. 17). These results showthat plasmid-mediated gene therapy in combination with conventionalprocedures such as debulking of tumor ascites may hold promise forfuture treatment of human ovarian cancer.

Dose-Response of IL-2 pDNA:lipid

A dose-response study was initiated to determine the minimum dose ofVR1110:lipid that could still result in a significant antitumor effect.C3H/HeN mice were injected with 25, 50 or 100 μg of IL-2 pDNA:lipid ondays 5, 8 and 11 after MOT tumor cell injection. A control group of MOTtumor-bearing mice were injected with 100 μg of VR1012 complexed withlipid. By day 15 post tumor cell injection, mice treated with either the50 or 100 μg dose of VR1110 complexed with lipid had a significantinhibition of tumor growth (p=0.002) compared to the mice treated withthe VR1012:lipid (FIG. 18A). A significant increase in survival (p=0.01)was also found for the mice treated with either the 50 or 100 μg dose ofVR1110:lipid (FIG. 18B). On day 25, none of the mice treated with theVR1012:lipid survived, while the mice injected with 50 or 100 μg ofVR1110:lipid had 27 and 33% survival, respectively. By day 37, micetreated with 50 or 100 μg of VR1110:lipid had 20 and 27% survival,respectively. Tumor-bearing mice treated with 25 μg of VR1110 complexedwith lipid were not significantly different from the control mice foreither tumor volume or survival.

Cytokine Profile of Ovarian Tumor Ascites

Since i.p. injection of IL-2 pDNA:lipid into mice bearing i.p. MOTtumors resulted in high levels of IL-2 expression in the ascites, it wasof interest to determine whether the IL-2 therapy initiated a cytokinecascade in the tumor ascites. C3H/HeN mice were injected i.p. with 105MOT cells. On days 5, 8 and 11 after tumor cell implant, the mice wereinjected i.p. with either VR1110:lipid or VR1012:lipid (1:1 pDNA:DMRIEmass ratio) or received no treatment after the MOT tumor cell injection.Two days after each injection of pDNA:lipid (days 7, 10 and 13 aftertumor cell implant), 5 mice per group were sacrificed and the tumorascites was collected. The total volume of ascites was determined permouse. The ascites samples were spun at 14,000 rpm for 2 minutesfollowed by collection of the supernatants. The ascites supernatantswere assayed for the concentration of the cytokines: IL-2, IL-4, IL-6,IL-10, IL-12, granulocyte-macrophage colony stimulating factor (GM-CSF),interferon gamma (IFNγ) and tumor necrosis factor alpha (TNFα) usingELISA (R & D Systems, Minneapolis, Minn.). The concentration oftransforming growth factor beta (TGFβ) in the ascites was assayed usingthe TGFβ₂ Emax Immunoassay System (Promega, Madison, Wis.). The amountof cytokine in the tumor ascites was calculated using the formula:cytokine concentration in pg/ml×ml of total ascites=pg of cytokine/totalascites.

As expected, tumor-bearing mice injected i.p. with VR1110:lipid had amarked increase in IL-2 levels with negligible levels in untreatedtumor-bearing mice or mice injected with the VR1012:lipid (FIG. 19A).The levels of IFNγ and GM-CSF were also markedly elevated in the micetreated with VR1110:lipid (FIGS. 19B and 19C). The IFNγ and GM-CSFlevels in these mice increased on days 10 and 13 after tumor cellinjection but not on the day 7 timepoint suggesting that this could bedue to IL-2 secretion. Some non-specific increase in IFNγ was also foundin the ascites of tumor-bearing mice after injection of theVR1012:lipid; however, by day 13, the levels of IFNγ in thetumor-bearing mice treated with VR1110:lipid were 6-fold higher than inthe mice treated with VR1012:lipid suggesting that expression of IL-2upregulates IFNγ production.

Levels of IL-6, TNFα and IL-10 were increased in both the IL-2pDNA:lipid group as well as the control pDNA:lipid group suggesting thatpDNA:lipid complexes may non-specifically stimulate production of theseparticular cytokines in the tumor ascites (FIGS. 19D, 19E, and 19F). Nodifferences were found for IL-4, IL-12 or TGFβ in the ascites from anyof the groups and levels of these cytokines were low (0-300 pg/ml forIL-4 and IL-12 and 0-2000 pg/ml for TGFβ, data not shown). For all ofthe cytokines evaluated, mice treated with control pDNA without lipid,IL-2 pDNA without lipid or with lipid alone had similar cytokine levelsas the untreated mice.

Intraperitoneal Injection of IFNα pDNA:lipid Enhances Survival

C3H/HeN mice were injected i.p. with 105 MOT cells to establish ovariani.p. tumors. The mice then received i.p. injections of 100 μg of VR4111(mIFNα) or VR1012 (control) complexed with DMRIE:DOPE cationic lipid ata 1:1 DNA:DMRIE mass ratio in a total volume of 1 ml saline. The micereceived the i.p. injections of pDNA:lipid on days 5, 8 and 11 aftertumor cell injection. The mice were weighed 3-6 times per week. Fifteenmice were included in each treatment group.

Mice bearing i.p. MOT tumors and treated with i.p. VR4111:lipid had asignificant increase in survival (p<0.006) compared to the micereceiving the control plasmid (FIG. 20B). No significant reduction intumor volume was found for the VR4111:lipid-treated mice (FIG. 20A).

Example 7 Selective Transfection of Malignant Cells in MurineIntraperitoneal Melanoma Tumor Model

The anti-tumor effect of DNA formulations with or without lipids inmouse i.p. melanoma model have been evaluated in the present example.

Cell Line and Tumor Model

B16F10 mouse melanoma cells were grown in vitro in DMEM and 10% FCS. Twohundred thousand B16F10 mouse melanoma cells were implanted i.p. inC57BL/6 mice in 1-3 ml saline using a 28 G1/2 needle and withoutpuncturing internal organs.

Preparation of Plasmid DNA:lipid Complexes

The plasmid DNA-cationic lipid formulations were prepared just prior touse. Equal volumes of DNA and DMRIE:DOPE (1:1) were mixed by swirling toachieve a target concentration of 0.5 mg DNA/ml, 100 μg DMRIE/ml and0.12 mg DOPE/ml as previously described (Parker et al, 1996. Saffran etal, 1998). The other cationic lipids were mixed similarly so that themass ratio of DNA to cationic lipid was 5:1 and the cationic lipid toDOPE molar ratio was 1:1. The formulated material was then vortexed athigh speed for 30 seconds and kept at room temperature until doseadministration.

CAT Assay

Tumor or other tissues were collected, immediately frozen in liquidnitrogen and ground into a powder using a reversible drill as described(Manthorpe, M., Hartikka, J., Vahlsing, H. L. and Sawdey, M.Quantification of plasmid DNA transfection in vivo. In GeneQuantification. F. Ferre, ed. Birkhauser, Boston, Mass., 1998 inpress.). The dry frozen powder was thawed and extracted in lysis bufferand high speed supernates assayed for CAT activity using a two-phasepartition assay as described (Sankaran, L. Analytical Biochemistry 200:180-186 (1992)).

Cationic Lipids Enhances Tumor Transfection

C57BL/6 mice were injected i.p. with 200,000 B16F10 murine melanomacells, and seven days later, injected i.p. with CAT pDNA(VR1332):DMRIE/DOPE. Two days later, tumor tissues were collected,extracted, and assayed for CAT activity.

As shown in Table 4, DNA alone transfected tumor, but DMRIE:DOPEincreased transfection by 78 fold (from 2,326 to 182,052).

TABLE 4 pgs CAT per gm of tumor tissue collected (n = 4 to 6 mice asindicated); saline values subtracted DMRIE, Mouse # DNA only DNA:DMRIEno DNA 1 0 82,600 0 2 307 137,551 0 3 706 220,600 0 4 791 287,458 0 55,892 0 6 6,258 Average 2,326 182,052 0 Std Error 1,306 52,140 0 Foldhigher 1 78 0

Selective Transfection of Tumor Cells

Normal animal. Normal, non-tumor bearing BALB/c mice were injected i.p.with 1 mg/2 ml VR1332, with or without a cationic lipid, and with orwithout the neutral lipid, DOPE. Two days later, selected i.p. tissues(liver, lung, kidney, spleen, mesentery) were collected, extracted, andassayed for CAT activity.

As shown in Table 5, normal intraperitoneal organs were not at alltransfected or transfected very little with a variety of cationiclipids: There was a low level transfection of mesentery tissues, and amoderate transfection of 1 of 5 spleens (the one transfected spleen mayhave been punctured by the injection needle).

TABLE 5 Average pgs CAT per gm of tumor tissue (avg., n = 5 mice) Salinebackground values have been subtracted + DMRIE, + βAE-DMRIE, ORGANS DNAonly + DMRIE + βAE-DMRIE + GAP-DLRIE + DOSPA no DOPE no DOPE Liver 0 0 00 0 0 0 Lung 0 0 0 0 0 0 0 Kidney 0 0 0 0 0 0 0 Spleen 0 2,563(0)* 0 0 00 0 Mesentery 370 1,549 1,866 1,127 600 1,091 3,604 *one mouse with aCAT value; the rest = 0

Tumor bearing animal compared to normal animal. C57BL/6 mice wereinjected i.p. with 200,000 B16F10 murine melanoma cells, and seven dayslater, injected i.p. with VR1332 with or without cationic lipid/DOPE.Two days later, selected i.p. tissues (liver, lung, kidney, spleen,mesentery) were collected, extracted, and assayed for CAT activity.

As shown in Table 6, tumor tissues were transfected at high levels withpDNA complexed with cationic lipid/DOPE. Normal i.p. organs were nottransfected well compared to i.p. tumor tissues.

TABLE 6 Average pgs CAT per gm of tumor tissue (n =5 mice); salinevalues subtracted DNA + DMRIE:DOPE DNA + normal mice ORGANS DNA onlyDMRIE:DOPE no tumors Tumor 0 200,195 n/a Liver 0 0 0 Lung 0 0 0 Kidney 00 0 Spleen 493 0 0 Mesentery 6,795 nd 2,562 Ovary nd nd 0

Dose Response

C57BL/6 mice were injected i.p. with 200,000 B16F10 murine melanomacells, and seven days later, injected i.p. with 0.15 or 1.5 mgs ofVR1332 with or without cationic lipid/DOPE in 3 ml saline. Two dayslater, tumor tissues were collected, extracted, and assayed for CATactivity.

As shown in Table 7, a higher dose of DNA transfected tumor tissuesbetter than a lower dose. Also, DMRIE transfected better than the twoother cationic lipids tested.

TABLE 7 Average pgs CAT per gm of tumor tissue (n = 5 mice); salinevalues subtracted DNA DOSE DNA only + DMRIE + GAP-DMRIE + PA-DELO  1.5mgs 16,592 1,270,466 524,006 581,616 0.15 mgs 1,937 131,089 47,86699,797

Testing a Variety of Cationic Lipids

C57BL/6 mice were injected i.p. with 200,000 B16F10 murine melanomacells, and seven days later, injected i.p. with 1 mg of VR1332 with orwithout cationic lipid/DOPE in 3 ml saline. Two days later, tumortissues were collected, extracted, and assayed for CAT activity.

As shown in Table 8, all cationic lipids tested increased transfectionlevel, and DMRIE was one of three preferred cationic lipids.

TABLE 8 Average pgs CAT per gm of tumor tissue (n = 5 mice); salinevalues have been subtracted CL:DOPE Run 1 Run 2 Average None 6,247 notdone 6,247 GAP-DDRIE 20,816 7,027 13,922 GMU-DMRIE 9,355 52,888 31,122HP-DORIE 36,615 26,795 31,705 DOSPA 33,494 57,026 45,260 PA-TELO 63,32632,681 48,004 GA-LOE-BP 59,729 63,528 61,629 GAP-DMRIE 80,760 63,00271,881 PA-DELO 73,692 82,265 77,979 GAP-DLRIE 77,553 107,629 92,591DMRIE 77,128 122,225 99,677 DLRIE 122,999 128,225 125,612 PA-DEMO155,369 154,884 155,127

In sum, the success of the intra-cavity delivery embodiment of thepresent invention is also exemplified in the murine melanoma tumormodel. Following i.p. injection of a polynucleotide, transfection occurspredominantly in tumor tissues, and normal intraperitoneal organs, suchas liver, lung, and kidney are poorly transfected, if at all, with thepolynucleotide formulation.

The following examples demonstrate the surprising finding thatcompositions comprising polypeptide-encoding polynucleotides and certainsalts and/or auxiliary agents can enhance subsequent gene expressionwhen administered into murine tissues.

Materials and Methods

The following materials and methods apply generally to all the examplesdisclosed herein. Specific materials and methods are disclosed in eachexample, as necessary.

Preparation of the Pharmaceutical Compositions

All salts used in the following examples are available from SigmaChemical Corporation (Sigma, St. Louis, Mo.). Detergents used in thefollowing examples are available from Sigma, Roche MolecularBiochemicals (Indianapolis, Ind.), BASF (Mount Olive, N.J.), and Amresco(Solon, Ohio). Purified plasmid DNA was ethanol precipitated andresuspended in water. Salt solutions were prepared as 300 mM stocksolutions and dilutions were made using sterile USP water (Baxter,Deerfield, Ill.).

Preparation of Plasmid DNAs

FIG. 21 depicts the major structural and regulatory elements containedin each plasmid. The gene for Photinus pyralis (firefly) luciferase wassubcloned from the pSP-LuC vector (available from Promega, Madison,Wis.) into the VR1012 vector (Manthorpe, M., et al., Hum. Gene Ther.4:419-431 (1993)) to make VR1223 or VR1255 (Hartikka, J., et al., Hum.Gene Ther. 7:1205-1217 (1996)). The RSV promoter-regulated VR1418 LacZvector was made by subcloning the LacZ gene from the VR1412 vector (Doh,S. G., et al., Gene Ther. 4:648-663 (1997)) into VR1043, itself derivedby replacing the CMV control elements of VR1012 with RSV controlelements. The mouse erythropoietin (EPO) was obtained by PCR asdescribed (Tripathy, S. K., et al., Proc. Natl. Acad. Sci. USA93:10876-10880 (1996)) and subcloned into the VR1012 vector to produceVR2901. The secreted form of the human placental alkaline phosphatase(SEAP) gene was subcloned from pSEAP2-Basic (available from Clonetech,Palo Alto, Calif.) into the VR1012 backbone vector to make VR3301. Therat preproinsulin coding sequence was obtained from reversetranscription of rat pancreatic preproinsulin poly(A) mRNA as described(Abai, A. M., et al., Hum. Gene Ther. 10:2637-2649 (1999)) and subclonedinto the VR1012 backbone vector to produce VR3502. The human IFN-ωcoding sequence was obtained by amplifying the coding sequence fromhuman genomic DNA prepared from DNA of fresh human blood. The mouseIFN-α gene was a generous gift from Paula Pitha-Rowe (Johns HopkinsUniversity). The IFN-ω and IFN-α genes were subcloned into the VR1055vector to produce, respectively VR4151 and VR4111 as described (Horton,H. M., et al., Proc. Natl. Acad. Sci. USA 96:1553-1558 (1999)). Theluciferase gene in VR1255 was replaced with the influenza A/PR/8/34nucleoprotein gene as described (Ulmer, J. B., et al., Ann. N.Y. Acad.Sci. 772:117-125 (1995)) to yield VR4700.

Plasmid DNA Purification

Plasmid DNA was transformed into Escherichia coli DH5α competent cellsand highly purified covalently closed circular plasmid DNA was isolatedby a modified lysis procedure (Horn, N. A., et al., Hum. Gene Ther.6:565-573 (1995)) followed by standard double CsCl-ethidium bromidegradient ultracentrifugation (Sambrook, J., et al., Molecular Cloning: ALaboratory Manual, 2nd Ed., Cold Spring Harbor Laboratory Press,Plainview, N.Y. (1989)). Alternatively, SEAP and preproinsulin encodingplasmid DNAs were purified using Giga columns from Qiagen (Valencia,Calif.) according to the kit instructions. All plasmid preparations werefree of detectable chromosomal DNA, RNA and protein impurities based ongel analysis and the bicinchoninic protein assay (Pierce Chem. Co.,Rockford Ill.). Endotoxin levels were measured using Limulus AmebocyteLysate assay (LAL, Associates of Cape Cod, Falmouth, Mass.) and wereless than 0.6 Endotoxin Units/mg of plasmid DNA. The spectrophotometricA260/A280 ratios of the DNA solutions were typically above 1.8. Plasmidswere ethanol precipitated and resuspended in water at 4° C. untilcompletely dissolved. DNA was stored at −20° C. until use. DNA wasdiluted by mixing it with 300 mM salt solutions and by addingappropriate amount of USP water to obtain 1 mg/ml plasmid DNA in thedesired salt at the desired molar concentration.

Injections of Plasmid DNA

The quadriceps muscles (or tibialis anterior muscles for SEAP plasmids)of restrained awake mice (female 6-12 week old BALB/c or Nude, nu/nu,from Harlan Sprague Dawley, Indianapolis, Ind.) were injected with 50 μgof DNA in 50 μl solution using a disposable sterile, plastic insulinsyringe and 28G 1/2 needle (Becton-Dickinson, Franklin Lakes, N.J., Cat.No. 329430) fitted with a plastic collar cut from a micropipette tip,all as previously described (Hartikka, J., et al., Hum. Gene Ther.7:1205-1217 (1996)). The tissues were extracted and assayed as describedin Manthorpe, M., et al., “Quantification of plasmid DNA expression invivo,” in Gene Quantification, Ferre, F., ed., F. Birkhäuser, Boston,Mass. (1998), pp. 343-368. Briefly, tissues were rapidly collected andfrozen, they were combined with and frozen into a lysis buffer, thetissue was then pulverized with a drill bit run in reverse direction,the resulting powder was thawed, and was extracted two times withextraction buffer. Nude mice were injected with VR3301 DNA bilaterallyon three consecutive days for a total of 300 μg DNA per mouse. Lungswere instilled with 132 μg plasmid DNA complexed with GAP-DLRIE/DOPE insolution and extracted all as described (Wheeler, C. J., et al., ProcNatl Acad Sci USA 93:11454-11459 (1996)).

Animal care throughout the study was in compliance with the “Guide forthe Use and Care of Laboratory Animals”, Institute of Laboratory AnimalResources, Commission on Life Sciences, National Research Council,National Academy Press, Washington, D.C., 1996 as well as with Vical'sInstitutional Animal Care and Use Committee.

Enzyme Assays

Luciferase activity was assayed using a Dynatech model ML2250 microplateluminometer (Chantilly, Va.) as previously described (Hartikka, J., etal., Hum. Gene Ther. 7:1205-1217 (1996)). The luciferase content of thesamples was calculated from Relative Light Units using a standard curveof purified firefly luciferase (Analytical Luminescence Laboratory,Sparks, Md., Cat. No. 2400), which was diluted in pooled extract fromuninjected muscles to control for quenching. Luciferase values wereexpressed as ng luciferase per muscle. The level of β-galactosidaseexpression in muscle extracts was quantified using a chemiluminescentassay according to the manufacturer's instructions (Roche MolecularBiochemicals, Indianapolis. IN, Cat. No. 1758241). A standard curve,prepared in pooled extract from uninjected muscles, was included on eachplate using the β-galactosidase enzyme standard included in the kit.

Sera from nude mice injected with VR3301 were collected at various timespost-injection. Five μl of serum was mixed with 15 μl distilled H₂O andplaced into individual wells of a 96 well plate (e.g., Costar EIA/RIAA/2 #3690, available from Corning, Inc). A serial dilution of EIA gradecalf intestinal alkaline phosphatase (CIP, available from RocheMolecular Biochemicals, cat. #567 744) in PBS containing 0.05% BovineSerum Albumin (BSA) was used to produce a standard curve. Samples wereassayed in duplicate. Plates were sealed, incubated at 65° C. for 30 minand spun for 5 min at 4000 rpm at room temperature. Each well received100 μl substrate solution containing 1 mg/ml para-nitrophenyl phosphate(PNPP, available from Roche Molecular Biochemicals, cat. #107 905) and 1mM MgCl₂ in 1M diethanolamine, pH 9.8. The samples were analyzed using aMolecular Devices Opti Max plate reader (Sunnyvale, Calif.). The platereader was pre-warmed to 37° C. and a standard kinetic program was usedto assay the samples at a wavelength of 405 nm for 30 min.

NP, Proinsulin, and β-Galactosidase ELISA

Sera were collected at different times before and after plasmid DNAinjections. Ninety-six well plates (available from Corning Incorporated,Acton, Mass., Cat. No. 3690) were coated with 36 ng/50 μl of BorateBuffered Saline (BBS)/well of NP purified from recombinant baculoviralextracts (available from Imgenix Corporation), commercial rat proinsulin(available from Crystal Chem, Chicago, Ill.) or 5 μl/50 μl ofβ-galactosidase protein (available from Sigma). The plates were storedovernight at +4° C. and the wells washed twice with Borate BufferedSaline Tween (BBST) (89 mM Boric Acid+90 mM NaCl, pH 8.3+234 mM NaOHsupplemented with 0.05% Tween 203® (v/v)). The wells were then incubated90 minutes with BB (BBST in which the Tween was replaced with 5% non-fatmilk in IX BBS) and washed twice with BBST again. Two-fold serialdilutions of mouse serum in BB starting at 1:20 were made in successivewells and the solutions were incubated for 2 hours at room temperature.Wells were then rinsed four times with BBST. Sera from micehyperimmunized with VR4700 NP. VR3502, or VR1412 plasmid DNA were usedas a positive control and pre-immune sera were used as negativecontrols.

To detect specific antibodies, alkaline phosphatase conjugated goatanti-mouse IgG-Fc (e.g., from Jackson Immunoresearch Laboratories, Inc.West Grove, Pa., Cat. No. 115-055-008) diluted 1:5000 in BBS were addedat 100 μg/well and the plates were incubated at room temperature for 2hours. After 4 washings in BBST, the substrate (1 mg/ml p-nitrophenylphosphate, e.g., from Calbiochem-Novabiochem Corp., San Diego, Calif.,Cat. No. 4876 in 50 mM sodium bicarbonate buffer, pH 9.8 and 1 mM MgCl₂)was incubated for 90 min at room temperature and absorbance readingswere performed at 405 nm. The titer of the sera was determined by usingthe reciprocal of the last dilution still giving a signal two timesabove background. Background was established using pre-immune serumdiluted 1:20. Serum concentrations of human IFN-ω were measured using acommercially available kit with a detection limit of 2 pg/ml (availablefrom Alexis Corp., San Diego, Calif.).

Hematocrit Measurements

Hematocrits were measured by centrifugation of blood obtained from theretro-orbital cavity of mice. Blood samples were collected in 75 μlheparinized capillary tubes and analyzed using HemaSTAT IImicrohematocrit centrifuge (Separation Technology, Inc., AltamoneSprings, Fla.).

Histology

For whole muscle staining, quadriceps were fixed for 3 hours at roomtemperature in 2% paraformaldehyde in PBS, washed 3 times for 20 mineach in PBS and incubated for 18 hours at 37° C. in a solutioncontaining 2 mM MgCl₂, 5 mM potassium ferricferrocyanide and 1 mg/ml5-bromo-4-chloro-3-indoyl-β-D-galactosidase (available from LifeTechnologies, Inc. (LTI). Gaithersberg, Md.) in PBS. After incubation,the muscles were washed 3 times for 10 min each in 3% dimethyl sulfoxidein PBS and stored in PBS at 4° C. until analysis. To prepare stainedtissue cross sections, quadriceps were snap-frozen in liquidnitrogen-cooled isopentane, cut in half, embedded in OCT medium(available from VWR, McGraw Park, Ill.) and 10 μm sections were cutusing a Jung Frigocut Model 2800E cryostat (Leica, Foster City, Calif.).Sections were collected on 1% gelatin coated glass slides, brought toroom temperature and stained for 2 hours at 37° C. in the same reagentas for whole mounts above except that the beta-galactosidase reagentconcentration was 200 μg/ml. The sections were then counterstained withHarris hematoxylin in acetic acid, rinsed in tap water, dehydrated andmounted in Permount (Fisher, Fair Lawn, N.J.). The number ofβ-galactosidase positive cells per muscle was determined by lightmicroscopy in muscle cross-sections as described (Doh, S. G., et al.,Gene Ther. 4:648-663 (1997)).

Splenocyte CTL Stimulation Cultures

To generate CTL effector cells from plasmid DNA immunized BALB/c mice,splenocytes were stimulated in culture for 5 days with NP₁₄₇₋₁₅₅ peptide(TYQRTRALV) pulsed, irradiated splenocytes from naïve BALB/c mice. Forthe stimulation cultures, splenocytes from naïve mice were γ-irradiatedwith 3200 Rads and pulsed with 10 μM of the H-2K^(d) restrictedNP₁₄₇₋₁₅₅ peptide for 40 min at 37° C. Then, 2.5×10⁷ test splenocytesfrom DNA immunized mice were incubated at 37° C. in 5.5% CO₂ with anequal number of irradiated, pulsed splenocytes from naïve mice in 25 cm²flasks containing 25 ml RPMI 1640 media with L-glutamine and 25 mM HEPESsupplemented with 10% fetal bovine serum, penicillin (100 U/ml),streptomycin (100 μg/ml) and 5.5×10⁻⁵ M β-mercaptoethanol). Tissueculture reagents are all available from LTI. After 24 hours of culture,recombinant murine IL-2 was added to a final concentration of 1 U/ml.

⁵¹Cr Release Assay

To measure specific lysis of NP₁₄₇₋₁₅₅ peptide pulsed target cells byCTL effector cells. P815 cells (available from the American Type CultureCollection, Manassas, Va.) were labeled with Na₂ ⁵¹CrO₄ (NEN LifeScientific Products. Inc., Boston, Mass.). Aliquots of ⁵¹Cr labeledcells were either pulsed with 10 μM NP₁₄₇₋₁₅₅ or were used unpulsed. Forthe CTL assay, stimulated splenocytes were serially diluted in 96 wellround bottom microtiter plates (available from ICN Biomedicals, Inc.,Aurora, Ohio). Target cells were added in a final volume of 100 μl/well.After incubation for 5 hours at 37° C. in 5.5% CO₂, 100 μl of RPMI 1640complete media was added to each well, the plates were centrifuged and100 μl/well was removed for analysis in a Cobra II gamma counter(Packard Instruments Co., Downers Grove, Ill.). The percentage ofspecific lysis was calculated as % specific lysis=(a-b/c-b)100 where ais the average cpm released in the presence of effectors, b is theaverage spontaneous cpm released from target cells incubated in mediaonly and c is the maximum cpm released from target cells in the presenceof 1% Triton X-100™.

DNase Inhibition Assay

Quadriceps muscles were harvested from naïve mice as previouslydescribed (Hartikka, J., et al., Hum. Gene Ther. 7:1205-1217 (1996)).Ten muscles were pooled and ground at 4° C. without adding buffer usinga Duall tissue grinder with ground glass pestle (Kontes Glass Co.,Vineland, N.J.), centrifuged at 13,000×g for 20 min, and the supernatantwas collected and stored at −20° C. Serum was collected from 10 naïvemice by orbital sinus puncture, pooled and stored at 4° C. For theassay, VR1255 DNA was diluted to 0.25 μg/ml in the respective solution,mixed with 0.1 volume of muscle extract or serum, and incubated at 37°C. for 2 hours. The samples were neutralized by adding an equal volumeof 2% sodium dodecyl sulfate+50 mM EDTA, and 4 μl of each sample wasanalyzed by electrophoresis on 0.8% agarose Tris Acetate EDTA gels withethidium bromide staining.

Statistical Evaluations

All statistical comparisons from tissue expression data were performedusing the non-parametric Mann-Whitney rank sum test (SigmaStat version2.03, Jandel Scientific Software, San Rafael, Calif.) and whereindicated by the standard Student T-Test. Differences by all statisticalmethods were considered statistically significant when the p value wasless than 0.05.

Example 8 Effect of Various Solutions Containing Sodium Chloride andSodium Phosphate on Luciferase Plasmid DNA Expression in Murine Muscles

The purpose of the present example is to demonstrate the ability ofcertain salt solutions to increase the levels of plasmid DNA expressionwhen injected into muscle compared with plasmid DNAs formulated innormal saline.

Mouse quadriceps muscles were injected with 50 μg of plasmid VR1223,encoding luciferase, dissolved in 50 μl of either water, saline, PBS,saline plus 100 mM sodium phosphate, 100 mM NaCl, or 100 mM NaCl plus 50mM sodium phosphate. The muscles were extracted and assayed forluciferase activity 7 days later. The results are shown in Table 9. Whenthe plasmid was dissolved in distilled water, luciferase expression was25-times lower than when the plasmid was dissolved in saline (4 vs. 119ng lux/muscle). Injection of the plasmid dissolved in PBS (i.e., salineplus 10 mM sodium phosphate) elicited a marginal, but statisticallyhigher 1.6-fold expression level than saline (186 vs. 119 ng luciferaseper muscle, p=0.02). Delivery of the plasmid in a hypertonic solutioncontaining saline plus 100 mM sodium phosphate reduced expression to thelevel obtained using saline alone (117 vs. 119 ng lux/muscle). Ahypoosmotic 100 mM NaCl solution yielded the same expression asisoosmotic saline (112 vs 119 ng lux/muscle), but restoration ofosmolarity by the addition of 50 mM sodium phosphate to the 100 mM NaClincreased expression by 1.8 fold (112 vs 203 ng lux/muscle, p=0.03).Thus, sodium phosphate increased luciferase expression.

Example 9 Effect of the Molar Concentration of Sodium Phosphate and pHon Luciferase Plasmid DNA Expression in Murine Muscles

The effect of sodium phosphate concentration and pH on the level ofluciferase expression from injected plasmid DNA in murine muscles wastested as follows. Plasmid VR1223 DNA was dissolved in solutionscontaining different concentrations of sodium phosphate in the absenceof NaCl, and these were tested for day 7 luciferase expression inquadriceps muscle as described in Example 1 above. The molarconcentrations of sodium phosphate tested ranged from 2.5 mM to 300 mM.The averaged data from 5 separate experiments are shown in FIG. 22A.Peak expression occurred when the plasmid DNA was dissolved in 150 mMsodium phosphate, which yielded 386 ng luciferase per muscle which is4.3-fold higher than the average expression level observed when the DNAis dissolved in saline (indicated by the dashed line at 89 ng luciferaseper muscle, p<0.001). The expression levels observed when the DNA wasdissolved in 80 mM, 100 mM, 150 mM, and 200 mM sodium phosphatesolutions were significantly higher than saline by Mann-Whitney rank sumtest (p<0.05). Injection of plasmid DNA dissolved in solutions havingsodium phosphate concentrations below 40 mM (in the absence of addedchloride ion) or above 300 mM resulted in luciferase expression levelsequal to or lower than those seen with saline.

To examine the effect of pH, plasmid VR1223 was dissolved in 150 mMsodium phosphate or potassium phosphate at pHs of 6.5, 7.5 or 8.0 andwas tested for day 7 expression in quadriceps muscle as described inExample 1 above. The results indicated that an optimal pH of about 6.5to 7.5, with pH 8.0 being suboptimal (FIG. 22B).

Example 10 Effect of Alternate Salt Solutions on Luciferase Plasmid DNAExpression in Murine Muscles

In this example, injection of plasmid DNA encoding luciferase dissolvedin 150 mM solutions of various salts which vary either the cation or theanion of normal saline were compared with saline for their ability tostimulate luciferase expression in murine muscle. The results are shownin Table 10.

Table 10A shows the effect on luciferase expression when the plasmid DNAis dissolved in a solution of a salt where the sodium cation in salineis replaced with other cations. Plasmid VR1223 dissolved in the varioussolutions was tested for day 7 expression, in quadriceps muscle asdescribed in Example 1 above. Two salts, ZnCl₂ and FeCl₂, were onlytested in 2 or 3 mice since these salts appeared to cause pain.Solutions containing divalent cations, e.g., magnesium (Mg²⁺), calcium(Ca²⁺), zinc (Zn²⁺) and ferrous iron (Fe²⁺), greatly decreasedexpression while the solution containing the monovalent cation potassium(K⁺) elicited the same expression as the monovalent sodium cation (Na⁺).

Table 10B shows the effect on luciferase expression when the plasmid DNAis dissolved in a solution of a salt where the sodium cation in sodiumphosphate was replaced with various other cations. Plasmid VR1223dissolved in the various solutions was tested for day 7 expression inquadriceps muscle as described in Example 1 above. Just as replacing thesodium cation in saline with potassium cation did not affect luciferaseexpression, replacing the sodium cation in sodium phosphate withpotassium cation also had no effect. Thus, a solution of 150 mMpotassium phosphate stimulated expression just as well as solution of150 mM sodium phosphate when both were compared with saline. Whenplasmid DNA was dissolved in 150 mM solutions of dibasic or monobasicsodium phosphate (not adjusted for pH), luciferase expression was onlyslightly stimulated over saline. The best stimulation of expressionoccurred when the plasmid DNA was dissolved in a 150 mM solution ofsodium or potassium phosphates which is a mixture of the dibasic andmonobasic forms balanced to achieve the desired pH (in this case, pH7.0). Other phosphate salts tested, i.e., when the cation was Mg³⁺,Ca³⁺, Aluminum (Al³⁺) or ferric iron (Fe³⁺) resulted in inhibitedexpression relative to saline.

Table 10C shows the effect on luciferase expression when the plasmid DNAis dissolved in a solution of a salt where the phosphate anion in 150 mMsodium phosphate was replaced with various other anions. Plasmid VR1223dissolved in the various solutions was tested for day 7 expression inquadriceps muscle as described in Example 1 above. Injection of theplasmid DNA in solutions of the sodium salts of acetate, pyruvate,bicarbonate and sulfate all increased luciferase expression comparedwith saline. Sodium citrate yielded the same luciferase expression assaline but sodium oxalate inhibited luciferase expression. Thus,according to Table 10C, stimulatory effects of various 150 mM saltsolutions can be ranked in order of their relative enhancement ofluciferase expression as follows: sodium phosphate=potassiumphosphate=sodium acetate>sodium pyruvate=sodium bicarbonate=sodiumsulfate>saline=potassium chloride=sodium citrate. The rest of thesolutions tested inhibited expression compared with saline.

The effects of osmolarity and pH on the ability of certain saltsolutions to enhance luciferase expression in murine muscle was testedas follows. The osmolarity and pH of each salt solution (150 mMconcentration unless otherwise indicated) shown in Tables 11-A and 11-Bwere measured and plotted vs. the 7-day luciferase expression levelobtained with that solution (FIGS. 22C and 2D). The pH values andosmolarities of the various salt solutions, as well as the relative7-day luciferase expression observed when plasmid VR1223 was dissolvedin each solution and injected into murine muscle, are shown in Table11-A and 11-B. The osmolarity graph (FIG. 22D) revealed that solutionswith osmolarities between 271 and 349 mmol/kg generally yielded thehighest expression levels but exceptions included 50 & 100 mM sodiumphosphate at 83 and 270 mmol/kg (respective expression levels 2.1 and2.3 fold those of saline at 310 mmol/kg) and sodium citrate at 394mmol/kg (expression level was the same as with saline). The 150 mMsodium phosphate solution yielded an expression level that was 4-foldhigher than that of saline, vet both solutions had the same osmolarity(310 vs. 308 mmol/kg, respectively). The pH graph (FIG. 22C) revealedthat the highest expression levels were generally obtained withsolutions at pH 6.0 to 7.5. However, some exceptions were sodiumsulfate, pH=5.5, and sodium bicarbonate, pH 9.0, which yieldedexpression levels that were 2.6 and 2.8-fold, respectively, over salineat pH 5.5. Furthermore, the magnesium phosphate solution had a pH=7.0but yielded an expression level lower than saline.

The reproducibility of enhanced luciferase DNA expression when theplasmid DNA is dissolved in a solution of 150 mM sodium phosphate wastested as follows. Nine different experiments were carried out to testluciferase expression levels when plasmid VR1223 was dissolved in 150 mMsodium phosphate for injection into mouse skeletal muscle. In each ofthe experiments, 10 quadriceps muscles were injected with 50 μg ofplasmid VR1223 in 50 μl of either saline or 150 mM sodium phosphate.Muscles were collected and assayed for luciferase expression at 7 days.The averaged results for each experiment are shown in FIG. 23. Comparedwith saline, sodium phosphate enhanced luciferase expression in all 9experiments, with the enhancement ranging from 2.5-fold (156 vs. 384 nglux/muscle for Exp. #9) to 7.3-fold (49 vs. 362 ng lux/muscle in Exp.#1). In these replicate experiments, the average enhancement by sodiumphosphate for all 9 experiments was 4.1-fold (120 vs. 490 ngluciferase/muscle).

Example 11 Expression of β-Galactosidase and Human Interferon-OmegaFollowing Intramuscular Injection of Plasmid DNA is Enhanced when thePlasmid is Injected in a Sodium Phosphate Solution

The effect of a sodium phosphate solution on the expression ofpolypeptides other than luciferase following intramuscular injection ofplasmid DNAs encoding the polypeptides was examined as follows. Plasmidsencoding non-secreted β-galactosidase (VR1418) and secreted humaninterferon-omega (IFN-ω; VR4151) in saline or 150 mM sodium phosphatewere injected into mouse quadriceps as described in the materials andmethods and Example 1. Muscle extracts were assayed for β-galactosidaseand the serum was assayed for circulating levels of IFN-ω. The 7 daypost-DNA injection protein expression data, including luciferase plasmidDNA run in parallel for comparison, are shown in FIG. 24. Injection ofthe plasmid DNAs dissolved in 150 mM sodium phosphate enhancedexpression of all three proteins over saline. Compared with saline,injection of plasmid DNA in 150 mM sodium phosphate enhanced expressionof luciferase in muscle by 4.8-fold (769 vs. 159 ng/muscle; p<0.001),β-galactosidase in muscle by 3.3-fold (9.8 vs. 3.0 ng/muscle; p=0.001)and serum IFN-ω levels by 2.5-fold (0.35 vs. 0.14 ng ml serum; p=0.020).

Plasmid DNA dissolved in PBS, run in parallel, elicited statisticallyequivalent expression as saline for the plasmids encodingβ-galactosidase and IFN plasmids (data not shown).

Plasmid DNA VR1418 encoding β-galactosidase was dissolved in sodiumphosphate solutions at the various molar concentrations tested inExample 2. Quadriceps muscles were injected with 50 μl of each solutioncontaining 10 μg of plasmid VR1418, and the muscles were tested for7-day expression levels. As with luciferase expression, as shown inExample 2, 150 mM sodium phosphate was the optimal molar concentrationfor β-galactosidase expression (data not shown). This similar effectoccurred despite the fact that the β-galactosidase gene on VR1418 isdriven by an RSV promoter, rather than the CMV promoter which drivesexpression of luciferase on plasmid VR1223 and IFN-ω on plasmid VR4151and despite the fact that 10 μg of plasmid DNA was injected per musclerather than 50 μg.

Example 12 Expression of Human Placental Alkaline Phosphatase, RatProinsulin and Mouse Erythropoietin Following Intramuscular Injection ofPlasmid DNA is Enhanced When the Plasmid is Injected in a SodiumPhosphate Solution

Three different plasmid DNAs encoding a secreted form of human placentalalkaline phosphatase (SEAP; VR3301), rat preproinsulin (VR3502) or mouseerythropoietin (EPO; VR2901) were injected into mouse skeletal muscle insaline or 150 mM sodium phosphate solutions as described in theMaterials and Methods and in Example 1. The mice were monitored overtime for blood levels of SEAP or proinsulin or for hematocrits. Theresults are shown in FIG. 25. In the case of SEAP, plasmid DNA wasinjected into the tibialis anterior muscles, and nude mice were used toprevent an immune response to the foreign transgene product. Thekinetics of blood SEAP levels from mice injected with DNA dissolved inboth saline and 150 mM sodium phosphate were similar. SEAP proteinexpression rose to a peak level at 7 days, then declined to 40-45% ofthe maximum expression level where it remained for two months. TheSodium phosphate solution significantly enhanced SEAP expression by 1.4to 1.8-fold compared with saline (n=15; p 0.002 to 0.037) over the timecourse. A parallel experiment using PBS showed expression to bestatistically equivalent to that obtained with saline (data not shown).Thus, injection of plasmid DNA dissolved in a 150 mM sodium phosphatesolution resulted in a higher level of sustained expression than whendissolved in saline.

Plasmid DNA encoding rat preproinsulin, dissolved in either 150 mMsodium phosphate or saline, was injected into the muscles ofimmunocompetent mice. Injection of the plasmid DNA in the sodiumphosphate solution enhanced expression over a 2 week period by 1.9 to3.8-fold compared with saline (n=10; p<0.01). Proinsulin expressioneventually declined to very low levels in both groups, possibly due tothe generation of measurable anti-proinsulin antibodies (data notshown).

Plasmid DNA encoding mouse EPO, dissolved in either 150 mM sodiumphosphate or saline, was injected into the muscles of immunocompetentmice. Hematocrit levels, which correlate with the expression oferythropoeitin, rose steadily over 4 weeks. Control mice injected with20 μg of DNA encoding canine Factor IX exhibited a constant hematocritaveraging 48. Injection of plasmid DNA dissolved in 150 mM sodiumphosphate solution resulted in higher hematocrit levels than theinjection of plasmid DNA dissolved in saline at all the time pointstested. This enhancement ranged from 1.4 to 2.1-fold (n 10; p0.02-0.001).

Example 13 Histological Analysis of Muscle Tissues Injected with PlasmidDNA Encoding β-galactosidase Dissolved in Either Sodium Phosphate orSaline

Individual muscle cells were examined for β-galactosidase expression asfollows. Twenty-six BALB/c quadriceps muscles each were injected with 50μg of plasmid VR1412 DNA (expressing β-galactosidase) in 50 μl of eithersaline or 150 mM sodium phosphate, according to the methods disclosed inthe Materials and Methods and in Example 1. The muscles were collected 7days later and stained for β-galactosidase. A quantitative analysis ofβ-galactosidase-stained fibers using previously detailed methods (Doh.S. G., et al., Gene Ther. 4:648-663 (1997)) revealed a significantlygreater number of β-galactosidase-stained myofiber cells in the sodiumphosphate group than in the saline group. Cell counts of sections takenfrom the midline of 20 muscles (10 muscles for each group) revealed thatthe sodium phosphate group contained more β-galactosidase-positivemyofiber cells than did the saline group (average of 108+/−21 vs.186+/−43 myofiber cells/muscle section; p=0.02; n=10). Thus, plasmid DNAdissolved in 150 mM sodium phosphate apparently has an enhanced abilityto transduce muscle cells relative to plasmid DNA dissolved in saline.

Example 14 Sodium Phosphate Inhibits Muscle DNase Activity

While not being bound by theory, the inventors believe that onemechanism by which sodium phosphate could enhance plasmid DNA expressionin muscle is by preventing or inhibiting DNA degradation. To assess thispossibility, aliquots of plasmid DNA in various aqueous solutions werespiked with mouse muscle extract or serum as described in the materialsand methods section, above. The reactions were incubated for 2 hours at37° C. in the presence of water, saline or 150 mM sodium phosphate.After incubation. DNA degradation was analyzed by agarose gelelectrophoresis. The results are shown in FIG. 26. Incubation of plasmidDNA in water with 10% v/v muscle extracts or serum resulted in thecomplete degradation of the DNA. Compare lanes 1 vs. 2 in FIG. 26. Asignificant amount of the DNA was protected in the presence of bothsaline and sodium phosphate. However, the sodium phosphate solutionprotected the DNA considerably better than did saline. Compare lanes 3and 4 in FIG. 26; note the presence of remaining closed circular form inthe muscle extract and the remaining nicked form in the serum for theDNA in the sodium phosphate solution. Similar results were obtained inreplicate experiments. This inhibition of DNA degradation correlateswith the increase in gene expression observed for DNA injected intomuscle (compare ng luciferase expression values taken form Tables I andII and shown at the bottom of each lane in FIG. 26 with the presence ofnicked and closed circular DNA).

Example 15 Plasmid DNA Immunization Utilizing a Sodium PhosphateSolution

The effect of sodium phosphate on the elicitation of an immune responseupon injection of plasmid DNA encoding an immunogen was examined asfollows. Mice were vaccinated intramuscularly with plasmid VR4700,encoding the influenza nucleoprotein. The DNA was dissolved in eithersaline or 150 mM sodium phosphate. The mice were monitored for thepresence of circulating anti-NP antibodies and for an NP-specificcytotoxic T lymphocyte response (CTL). The antibody data at 6 weeks andCTL data at 9 weeks post-vaccination are shown in FIG. 27. FIG. 27Ashows that in three replicate experiments (labeled 1-3, n=10 mice perexperiment), the sodium phosphate solution enhanced serum anti-NPantibody titers compared with saline solution. The enhancement by sodiumphosphate was significant in all 3 experiments (p<0.04) as well as inthe average of all three experiments (p<0.001). Plasmid VR VR4700,injected in PBS, was run in parallel and the antibody titers were notstatistically different from the plasmid injected in saline (data notshown). FIG. 27B shows that anti-NP specific CTL activity wasstatistically similar (p>0.05) in the saline and 150 mM sodium phosphategroup. A repeat set of CTL experiments showed the same result (data notshown).

Example 16

Polypeptide Expression in a Non-Muscle Tissue is Enhanced by Use of aSodium phosphate Solution and a Cationic Lipid for Delivery of PlasmidDNA

The effect of a sodium phosphate solution on the enhancement ofpolypeptide expression from plasmid DNA delivered to a non-muscle tissueusing a cationic lipid was evaluated as follows. Mouse lungs wereinstilled with plasmid VR1223 encoding luciferase combined with thecationic lipid GAP-DLRIE and co-lipid DOPE in water or selectedconcentrations of sodium phosphate as described in the Materials andMethods above. The use of DNA lipid complexes in water and collection atday 3 were previously found to yield peak lung transfection (Wheeler, C.J., et al., Proc Natl Acad Sci USA 93:11454-11459 (1996); Sawa, T., etal., Hum. Gene Ther 7:933-941 (1996)). The results are shown in FIG. 8.The level of luciferase expression in lung when the plasmid/lipidmixture was delivered to the lung in water (0.94 ng lux/lung) iscomparable with published reports (Wheeler, C. J., et al., Proc NatlAcad Sci USA 93:11454-11459 (1996)) and is considerably below the levelof expression obtained in muscle tissue using the same vectors withoutlipid. Unlike with muscle, when the plasmid/lipid mixture was deliveredto the lung in a 150 mM sodium phosphate solution, luciferase expressionwas inhibited compared with water (0.22 vs. 0.94 ng lux/lung; p<0.001).However, when the plasmid/lipid mixture was delivered to the lung in a2.5 mM sodium phosphate solution, luciferase expression was enhanced by5.5-fold compared with water (5.2 vs. 0.94 ng lux/lung; p<0.001).Intermediate to these values, when the plasmid/lipid mixture wasdelivered to the lung in a 10 mM sodium phosphate solution, luciferaseexpression was enhanced compared with water, but not as much as with 2.5mM sodium phosphate. When the plasmid/lipid mixture was delivered to thelung in saline, luciferase expression was inhibited compared with water(0.14 ng lux/lung; data not shown). Thus, sodium phosphate enhancesluciferase expression upon delivery of a plasmid DNA/lipid mixture inlung, but does so at a much lower sodium phosphate molar concentrationthan is effective in muscle.

TABLE 9 Effects of Selected Sodium Chloride Vehicles on LucifreasePlasmid DNA expression in Muscle ng Lux ± Std. Fold per Muscle Error nSaline Salt Solution 4 1 30 0.03 Double-distilled water 119 6 413 1.0150 mM Sodium Chloride (saline) 186 11 357 1.6 150 mM Sodium Chloride(saline) + 10 mM Sodum Phosphate (PBS) 117 64 20 1.0 150 mM SodumChloride (saline) + 100 mM Sodium Phosphate 112 38 20 0.9 100 mM SodiumChloride 203 42 40 1.7 100 mM Sodium Chloride + 50 mM Sodium Phosphate

TABLE 10 Effects of Selected Vehicles on Lucifrease Plasmid DNAexpression in Muscle ng Lux/ ± Std. Fold Muscle Error n Saline SaltSolution Formula A. Chloride Salts at 150 mM 119 6 413 1.0 SodiumChloride NaCl 124 32 10 1.0 Potassium KCl Chloride 1 0.4 10 <0.1Magnesium MgCl₂.6H₂O Chloride 0.3 0.2 10 <0.1 Calcium ChlorideCaCl₂.2H₂O 0.1 0.1 6 <0.1 Zinc Chloride ZnCl₂ 0.0 0.0 4 <0.1 FerrousChloride FeCl₂.4H₂O B. Phosphate salts at 150 mM 481 36 120 4.0 SodiumNaH₂PO₄/ Phosphate K₂HPO₄ 282 56 20 2.4 Sodium -- dibasic Na₂HPO₄ 198 4420 1.7 Sodium -- Na₂HPO₄ monobasic 449 40 20 3.8 Potassium KH₂PO₄/K₂HPO₄Phosphate 22 6 8 0.2 Magnesium MgHPO₄.3H₂O Phosphate 12 2 8 0.1 CalciumCaHPO₄ Phosphate 4 1 8 <0.1 Aluminum AlPO₄ Phosphate 0.4 0 10 <0.1Ferric Phosphate FePO₄ C. Sodium salts at 150 mM 119 6 413 1.0 SodiumChloride NaCl 481 36 120 4.0 Sodium NaH₂PO₄/ Phosphate Na₂HPO₄ 498 11910 4.1 Sodium Acetate C₂H₃O₂Na.3H₂O 364 64 19 3.1 Sodium PyruvateC₃H₃O₃Na 330 47 20 2.8 Sodium NaHCO₂ Bicarbonate 312 83 10 2.6 SodiumSulfate NaSO₄ 90 25 14 <0.1 Sodium Citrate C₆H₅Na₃O.2H₂O 15 2 8 <0.1Sodium Oxalate C₂O₄Na₂

TABLE 11-A Salt PH lux Zinc Chloride 5.0 0.1 Ferrous Chloride 5.0 0.0Aluminum Phosphate 5.0 4 150 mM NaCl (Saline) 5.5 119 100 mM NaCl 5.5112 Potassium Chloride 5.5 124 Magnesium Chloride 5.5 1 Calcium Chloride5.5 0.3 Sodium Chloride 5.5 119 NaP -- monobasic 5.5 198 Sodium Sulfate5.5 312 Calcium Phosphate 6.0 12 Sodium Pyruvate 6.0 364 FerricPhosphate 6.5 0.4 Sodium Acetate 6.5 498 Sodium Oxalate 6.5 15 MagnesiumPhosphate 7.0 22 Saline + 10 mM Na-P (PBS) 7.2 186 75 mM NaCl + 75 mMNa-P 7.2 177 50 mM Sodium Phosphate 7.2 254 100 mM Sodium Phosphate 7.2270 150 mM Sodium Phosphate 7.2 481 Sodium Phosphate 7.2 481 PotassiumPhosphate 7.5 449 Sodium Citrate 7.5 108 50 mM Sodium Citrate 7.5 83NaP - dibasic 8.0 282 Sodium Pyrophosphate 9.0 3 Sodium Bicarbonate 9.0330

TABLE 11-B Salt Osm lux Calcium Phosphate 36 12 Aluminum Phosphate 37 4Magnesium Phosphate 39 22 50 mM Sodium Phosphate 83 254 50 mM SodiumCitrate 164 83 Ferric Phosphate 165 0.4 100 mM NaCl 215 112 100 mMSodium Phosphate 232 270 Sodium Acetate 271 498 Sodium Pyruvate 271 364Sodium Bicarbonate 727 330 NaP - monobasic 277 198 Potassium Chloride280 124 150 mM NaCl + 10 mM Na-P 292 186 (PBS) 75 mM NaCl + 75 mM Na-P308 177 150 mM Sodium Phosphate 308 481 150 mM NaCl (Saline) 310 119Potassium Phosphate 323 449 Sodium Oxalate 346 15 Sodium Sulfate 349 312NaP - dibasic 357 282 Zinc Chloride 358 0.1 Magnesium Chloride 360 1Calcium Chloride 362 0.3 Ferrous Chloride 362 0.0 Sodium Pyrophosphate363 3 Sodium Citrate 394 108

It clear that the invention may be practiced otherwise than asparticular described in the foregoing description and examples.

Numerous modifications and variations of the present invention arepossible in light of the above teachings and, therefore, are within thescope of the appended claims.

The entire disclosure of all publications (including patents, patentapplication, journal articles, laboratory manuals, books, or otherdocuments) cited herein are hereby incorporated by reference.

1. A method of treating cancer or metastasis thereof in a mammal,comprising: administering into a muscle of a mammal with cancer ormetastasis thereof, a DNA plasmid comprising a polynucleotide whichencodes interferon-alpha or an active fragment thereof, operablyassociated with a promoter; wherein said muscle has not been treatedwith an agent that destroys muscle tissue; wherein said DNA plasmid isadministered free from ex vivo cells; wherein said interferon alpha isexpressed in vivo, and is present in the blood stream of said mammal inan amount effective to treat said cancer, or metastasis thereof.
 2. Themethod of claim 1, wherein said plasmid further comprises apolyadenylation signal and transcription termination signal operablyassociated with said polynucleotide.
 3. The method of claim 1, whereinsaid cancer is selected from the group consisting of renal cellcarcinoma, colorectal carcinoma, lymphoma, Kaposi's sarcoma, melanoma,prostate cancer, ovarian cancer, lung cancer, liver cancer, head andneck cancer, bladder cancer, uterine cancer, bone cancer, leukemia,breast cancer, non-melanoma skin cancer, glioma, solid cutaneous tumor,epidermoid carcinoma, metastases of any of thereof, and combinations ofany of thereof.
 4. The method of claim 3, wherein said cancer is a lungmetastasis of any of said cancers.
 5. The method of claim 3, whereinsaid cancer is a liver metastasis of any of said cancers.
 6. The methodof claim 1, wherein said muscle tissue is skeletal muscle.
 7. The methodof claim 1, wherein said interferon alpha is a polypeptide comprisingamino acids 1 to 166 of SEQ ID NO:10.
 8. The method of claim 7, whereinsaid interferon alpha is a polypeptide comprising amino acids −23 to 166of SEQ ID NO:10.
 9. The method of claim 1, wherein said DNA plasmid isVR4112 (SEQ ID NO:2).
 10. The method of claim 1, wherein said cancer ismelanoma or metastasis thereof.
 11. The method of claim 10, wherein saidcancer is metastasis of melanoma.
 12. The method of claim 11, whereinthe metastasis of melanoma is lung metastasis.
 13. The method of claim1, wherein said cancer is glioma.
 14. The method of claim 1, whereinsaid cancer is epidermoid carcinoma.
 15. The method of claim 1, whereinsaid DNA plasmid is dissolved in an aqueous solution.
 16. The method ofclaim 1, wherein said DNA plasmid is administered free from associationwith transfection-facilitating proteins, viral particles, liposomes,cationic lipids, and calcium phosphate precipitating agents.
 17. Themethod of claim 1, wherein said DNA plasmid is administered as a complexof said DNA plasmid and one or more cationic compounds selected from thegroup consisting of cationic lipids, cationic peptides, cationicproteins, cationic polymers other than lipids or peptides, and mixturesthereof.
 18. The method of claim 17, wherein said one or more cationiccompounds are one or more cationic lipids.
 19. The method of claim 18,wherein said compounds further comprise one or more neutral lipids. 20.The method of claim 1, wherein said DNA plasmid further comprises aregion regulating expression operably associated with saidpolynucleotide.
 21. A method of treating cancer, or metastasis thereof,in a mammal, comprising: the method of claim 1 in combination with oneor more additional cancer treatment methods selected from the groupconsisting of surgery, radiation therapy, chemotherapy, immunotherapy,and gene therapy.
 22. The method of claim 21, wherein said DNA plasmidis administered prior to the commencement of said one or more additionalcancer treatment methods.
 23. The method of claim 21, wherein said DNAplasmid is administered during the practice of said one or moreadditional cancer treatment methods.
 24. The method of claim 21, whereinsaid DNA plasmid is administered after the end of said one or moreadditional cancer treatment methods.
 25. The method of claim 1, whereinsaid mammal is human.
 26. A method of treating cancer in a mammal withcancer or metastasis thereof, comprising: administering into theperitoneal cavity of said mammal, a DNA plasmid comprising apolynucleotide which encodes interferon alpha or an active fragmentthereof, operably associated with a promoter, wherein said DNA plasmidis administered free from ex vivo cells or ex vivo cellular material;and wherein said interferon alpha is delivered to a tumor, or metastasesthereof, in a therapeutically effective amount.
 27. The method of 26,wherein said tumor disseminates in said peritoneal cavity.
 28. Themethod of claim 26, wherein said DNA plasmid is free from associationwith transfection-facilitating proteins, viral particles, and calciumphosphate precipitating agents.
 29. The method of claim 26, wherein saidDNA plasmid is administered as a complex with one or more cationiclipids.
 30. The method of claim 29, wherein said complex furthercomprises one or more neutral lipids.
 31. The method of claim 30,wherein said DNA plasmid is complexed with(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propaniminiumbromide and 1,2-dioleoyl-glycero-3-phosphoethanolamine.
 32. The methodof claim 26, wherein said mammal is a human.
 33. A method oftransfecting malignant cells in a mammal with cancer or metastasisthereof, comprising: administering into the peritoneal cavity of saidmammal, a DNA plasmid comprising a polynucleotide encoding interferonalpha, or an active fragment thereof, operably associated with apromoter, wherein said DNA plasmid is administered free from ex vivocells or ex vivo cellular material; and wherein said plasmid isdelivered to and expressed in malignant cells within said peritonealcavity.
 34. The method of claim 33, wherein said DNA plasmid is freefrom association with transfection-facilitating proteins, viralparticles, and calcium phosphate precipitating agents.
 35. The method ofclaim 33, wherein said DNA plasmid is administered as a complex with oneor more cationic lipids.
 36. The method of claim 33, wherein saidcomplex further comprises one or more neutral lipids.
 37. The method ofclaim 36, wherein said DNA plasmid is complexed with(±)-N-(2-hydroxyethyl)-N,N-dimethyl-2,3-bis(tetradecyloxy)-1-propaniminiumbromide and 1,2-dioleoyl-glycero-3-phosphoethanolamine.